updated 12/2006
     During the time that I have been restoring clubs for play, I have tried to use grip materials that were authentic to the period. A grip I have been using on all eras of hickory clubs is a leather grip I cut from "deer tanned" calf skin. Deer tanning is an oil tanning process that generally gives you a tacky grip. The problem with most new skins is that they have been coated with a poly coating for furniture and clothing applications, and that makes them very slippery for use as grips. You will find that you need to personally choose your own skins. I purchase my skins through the Leather Factory and the "deer tanned" Calf skin is part #9124. I also purchase my Whipping thread from this company and it is #1220-01. A whipping puller can be purchased from Sonny Chappie <skchappie@gogreatlakes.com>
The one "replica" that became available in recent years is a wrap-on rubber grip. Rubberized linen wrap-on grips were very popular in Great Britain in the last 40 years of the hickory era. I have used (but have discontinued using) a synthetic leather wrap grip made by Winn Golf even though it replicates the rubberized linen grips of the period very well. If you plan on playing in formal hickory events you will want to check the rules to see if they are allowed. I have discontinued using these grips because of conflicts with some of the events.
My personal grip of choice is the Grip Master leather wrap-on grip. Its characteristics for play I think are comparable to some of the choices that were available back in the era.
I know of some club restorers that are using coarse suede leather, whipping, tar, and other things to make the grips more substantial to the touch.
I have been playing wood shafted clubs for about twelve years, exclusively for about ten years, and have done so in all kinds of conditions. Unless they are waterproofed, most leather grips will become unusable after getting wet. For the serious hickory player, waterproofed or water resistant grips are to be considered essential. Lexol used regularly on your "new" or original smooth leather grips will help keep them tacky and resistant to moisture. You should clean original smooth (not suede) leather grips with a leather cleaning product before you try to soften them with a leather conditioner such as Lexol. The cleaning and conditioning will help in the removal of original grips if you plan to rewrap them or salvage them for use on other clubs that need an original type of grip.
I recommend using friction tape as an underlisting material for building up and shaping the grips on 20th century clubs. It is very easy to use to get the listing built up to the right thickness and taper before you wrap the grip material on. Using friction tape as a listing material is also authentic to the period as many of the original grips I have removed have had friction tape used as the listing material.
The thick woolen strips used so commonly for earlier clubs can be used also, but the shaft will need to be coated with an adhesive before wrapping it on. You will then want to coat the listing with the adhesive before wrapping the leather on top of it. Without the adhesive, the fabric listing and leather will stretch and loosen very quickly from use.
A dial caliper is very helpful in matching the grip build-up on a set of clubs. Be aware that as you build up the thickness of the grips, the swing wieght will be reduced. In period reference material has stated that they tried to keep the grips as small as possible so that they would have the maximum club head feel. I do occasionally use short strips of friction or hockey tape, wrapped in layers at the butt end of the club, to add increase the taper of the shaft. It was very common for this to be done on clubs in the late 20's and 30's and adds a level of comfort for those players that like to hold the club near the end of the club.
There are a couple of alternatives for grips. One is to do it yourself, buy skins and cut them, or to purchase ready made strips from others. I personally cut grips for about ten years and keep a stock of them. Now, I have changed to The Grip Master grip and am using them exclusively. The leather wrap-on grips they have replicate some of the grips that were produced in the late 1920's and forward. The dipping process they use on the leather gives a great tack to the grip that holds up quite well in all kinds of weather. They are very similiar in the way they are installed to the other grip except that the windings need to overlap slightly, where the cut leather actually needs to butt against eachother as they are wound down the shaft. The difference between the two is fairly significant in cost with the cut grips being considerably less expensive but not having the durability and tackiness of the other grip.
Grip cutting guide for calf skin hides
Based upon the old grips that I have removed and stories that I have read by old club makers, strips were cut to get the most out of a skin as possible with little regard to any standard for the width, length and taper. Saying that, I do have target dimensions for the strips that I cut. My strips are cut to taper from 1 5/8" to 1 1/4" over a length of 29 inches. These dimensions will give you a grip that is about 14 inches in length when wrapped on an underlisting that measures 3/4 of an inch in diameter at a point four inches down from the butt end of the shaft. The length of the grip after being wrapped on the shaft is very much a matter of personal taste. The grip length varied considerably back then, but 13 inches seems to be an average, but some grips were put on and covered as much as half the length of the shaft. On the irons that I expect to grip down on to pitch or chip with, I will extend them to 16 inches.
To cut a skin into grips you will need: the skin, a large sheet if mat board, a 4 foot steel ruler, a 1 foot ruler, a mat knife or exacto knife, and a great deal of patience. Part of getting the skin is in choosing one that you can get the most grips out of. A split or side is half the cow and they usually are about 4-7 feet long (head to tail) and vary from 1-4 feet wide (back bone to belly). You want as much length at a minimum of 26" wide, as you can get. When you are ready to start cutting, spread the skin out on the mat board, useing it as your cutting surface. The direction to cut is across the width, from the back to the belly. Use the 4' steel ruler as you cutting guide and the 1' ruler to measure your starting and ending widths. You can also cut a template from the mat board of the grip shape you want, to help guide the placement of the steel ruler for the cuts. Maintain good preassure on the blade of the knife and on the steel ruler throughout the cut. I will cut about 8-12" and then carefully shift my hand that is pressing down the steel ruler to the next 8-12" of cut until I cover the complete length. It is very important the leather not shift or slide around during the cut. It takes a little practice to learn how to get a nice, clean and straight cut the full length the grip.
Wrapping on a grip like everything else in restoring these clubs takes practice.
After building up the grip area with a listing material, select a strip of leather and cut a taper in the end similiar to the photo above. The length of the taper needs to be about a half of an inch longer than the diameter at the very end of the butt of the shaft. I find that the length of that cut is almost identical to the length of the blade of the steel sewing scissors that I use to cut it. This will give you about a half of an inch overlap as you start winding the grip down the shaft.
Nail the tip end at the end of the butt and wrap the taper edge along the outside of the butt. You will see that the leather starts angling down the shaft. After the leather overlaps just keep wrapping down and around the grip end of the shaft keeping the edges butted together if you are using cut grips, and overlapping slightly if you are using the Grip Master grips. The cut grips will have required one wrapping of friction tape, which is sticky on both sides, that will hold the cut grip in place. The Grip Master grip has tape already on it and needs to have the backing peeled off as you wrap it on into place. I like to wrap down to where the old grip used to finish and nail it in place there. Both grips will need to be cut square around the shaft at that point. The Grip Master grip might require some additional leather to reach that point. This can create the opportunity to add a decorative element by using a different color leather. In both cases, the ending of the leather will require the use of an exacto knife to taper the edge so that the whipping can transition up onto the leather from the wood.
There are many options for doing additional decorative whipping.
On a historical note: 
    In an original catalog for the St. Andrews Golf Co., they had a surprising range of offerings. They were offering grips made of Calfskin, Pigskin, and Rubber. All the grips were offered as strips to be wrapped on, except for one sewn leather version of a slip-on grip. The calfskin and pigskin grips were offered in Black, Red, Violet, Green and Brown colors. I have seen some very bright colored grips on the clubs that I have obtained. The origional color can sometmes be found under an overlap in the leather, were it might not have been worn or faded away. Other clubs have considerable color left in the original grips, as they must not have seen much play and/or were well taken care of.
After doing a little cleaning on some of the smooth "black" grips, some very vibrant colors have emerged. I have found many of the previously mentioned colors of leather hiding under all that dirt. We like to think of those times in black and white, but it seems that they enjoyed dressing up there clubs too.