how do i make object rotate

also how do i make it go in a given direction and determine the speed.

You can make an object appear to rotate by using the llTargetOmega function:

http://www.lslwiki.net/lslwiki/wakka.php?wakka=llTargetOmega

It's a client-side rotation only though, so everybody viewing it might see it slightly differently. It can also appear to stop rotating if you move too far away from it.