on a serious note, after the best man speech i done, i started school shortly after (im 27) and had to do presentations in front of the class a few times, same again shitting myself ect (ive been in the welding game 12 years so definitely not what im used to)
after a while i became more confident, it helped a lot.
use post cards for the speech, with bullet points or key words and talk around it. its a bit more relaxed, but it works a treat.
this is what i done last month for the speech at my own wedding and it went very smooth (if i say so myself)
you'll be grand.