To keep count you can use a Satanic rosary, sticks, cards, a calculator (type in 1+1 and hit the = button each time you do a vibration), folding a sheet of paper, or any other method that works for you. At the simplest, a Satanic rosary is just 108 beads on a string to help you keep count.
Here is a method originally posted by Fire2U (SuryaPuttran):
“To help you to keep-up with the count, find a way, practice it and familiarize yourself with it.
I use my fingers and finger-pads. There are 3 pads on each finger.
I use my thumb to press the 1st pad of my little finger for one count, 2nd pad of little finger for 2 counts, 3rd pad of my little finger for 3 counts.
Then i'll switch my thumb to press my ring finger's 1st pad for the 4th count and so on.
-I find using fingers to be very easy esp to count 108.
-I-'m right-handed so I'll press my thumb on each 3 pads of my right hand fingers which will amount to 12 counts (beginning with little finger then ring, middle and index),
-I'll press the pads of my LEFT hand's little finger to denote 1 set of 12 counts being done on my right.
So pressing 9 pads with my left thumb(begin with little finger, then ring then middle) on left hand X 12 counts on right hand = 108.”