I usually organise my programmes as such:
@MAINsetup
(bgm and initialisation here)
@MAINdraw
(spu and if statements commands go here)
goto @MAINcontrol
@MAINcontrol
("if button()" commands go here)
goto @MAINdraw
Set sprites using SPSET. Move them using SPOFS. There are too many commands that involve sprites to list them all here, but all of them start with SP. However, you should really concentrate on SPSET and SPOFS. Explanations for these are also a bit long, but you can find all the information you need in their respective help entries. (Position the cursor on top of the command and press [ ? ])