If your fondant gets too soft due to heat, try kneading in a little CMC/gum trag to help stabilize it. Also, if you fondant seems too dry or it is cracking, knead in a bit of white vegetable fat (Trex/Holsum), and like Sameera said above, roll your fondant a little thicker than usual, it will help keep it from tearing. Just take a deep breath, and go slow and steady, you will get it!
Cakes by lili --- Bloemfontein, South Africa