I like 12 mainly plus 3, 4 and 6. I count 3 6 9 12 15 18 21 24, 4 8 12 16 20 24, 6 12 18 24.. And sometimes count upto 144, in either of these increments. Usually when i count i run my tounge across my teeth, hitting 4 at a time and continuing around my mouth.. Or I run my thumb across my fingers in between my knuckles, using each section as a sort of counting block.
In grade 5 we played a game we called maths football, we were given basic equations to work out, if your team player got it correct first you moved further up the field to the goals, so you had to be fast. My teacher had asked me how I was working out the maths problems, I think I was doing quite well, I told him I was using my teeth!! How strange would it be to hear that?? I must have been getting equations that were related to my numbers.