From being a musician, it is easy to keep track of doing things either 3 or 4 times. So this is the way I do it. Count to 4, 4 times, and that is 16. I do this 6 times, and that is 96. Then do one time either 4x3 or 3x4, and this 12 more makes it 108. Some times I do the 12 one first so I don't mess up and accidently do it 16 times instead.
So (1234, 1234, 1234) this is 12. Then do (1234, 1234, 1234, 1234) this is 16, do this 6 times. You get in the pattern of it, and it becomes subconscious. You won't need to think about it much, and it will be easy to keep track of. This is the easiest way for me to do it.