Marbles also work. Having a dish of marbles (or those glass beads you can get at a dollar store, or dice… or anything, really) in one dish or jar and moving them to the other every time you do a slice of work is a nice way to keep track, too. @dreev has a bracelet that has beads on it that he can slide from one side to another to keep track of things.
I used to have a way overcomplicated set-up that would approximate how much time a goal would need given the units left to do and put an appropriately-sized event into a dedicated calendar. Don’t do that. (Also, I’ll post about it when I inevitably do it again so that if you want to, you can do that.)