[3.2 BSC] Cold-to-Fire Ice Trapper [from Budget (~10c) to expensive gears]

I have my first ever PoE character (1 in season, 1 in hardcore season) and am following this guide.

Could you tell me what 3 gems are best for Fencoil (Mirebough)

Also, I see the tree is different for 3.3, I went ahead and trained into the 3 trap skills on far right of tree... is that ok?

What stats should I be looking for in items?

Thank you