You will want to do this without getting your hands crossed. Try to determine the easiest way to play a tune when starting to learn it. This may help avoid having to relearn the hammering pattern as you attempt to play more rapidly. Many things have been used for hammers. Bent pieces of cane or curved sticks are perhaps the simplest.
Most hammers consist of thin handles with knobs on one end.
Handles may be made from tortoiseshell, whalebone, spring metal, wood, and old corset stays. The knobs or hammer heads are usually wood, sometimes with a covering of leather or felt. Sticks with felt pads for hammers give a soft sound but can be hardened by dipping in thinned lacquer or shellac for a loud, crisp tone. Try making different kinds to discover what feels best to you. Hammers are usually held between thumb and forefinger or between the forefinger and long finger on each hand.