OK, what do you experts do?

I signed up for a "triathlon." That is, do a full triathlon over the course of one month. Should NOT be a problem. The problem comes with counting the laps. I have a really nice walking/running track and swimming pool at the gym that I'm planning on using, but it is so repetative that I lose count of the laps.

So, how do I keep track of the distance I walk/run & swim? Surely there are tricks.

The bike part is no problem. I wish Cateye made swim computers. . .