good advice in the safety deal - -you don't want to breathe in any bad stuff, so a well places fan is a good - to have item (and it helps keep you cool - what's not to like?) I use heavy leather gloves (reserved for nothing other than casting) and I always wear long sleeves and good work boots.
Don't use an aluminum pot to melt your lead - a catastrophic failure is possible - not sure of the science, but I've heard from more than a few sources (none of whom have any vested interest in aluminum vs. iron) that there's something about the chemistry between lead and aluminum under heat which weakens the pot. very very very bad ju ju
Also, you should wear a hat or bandanna or "drive- on rag" of some sort: if a drop of sweat falls into the molten lead, the resulting splashback (caused by the near instantaneous conversion of the sweat to steam) will splatter bits of molten lead all over.
this will really interrupt your concentration
of course, don't eat, drink or smoke anything while casting, and wash up carefully when you're done.
I remember when I got started, it took about a thousand ball to amortize the cost of all my gear (molds, pots, melters, ladles, gloves and so on) and that didn't count the cost of shipping, which can get pretty steep pretty quick, so it's well worth the investment.
good luck with your project!