It's nice to have a low speed, smooth idle.. it's quiet and saves fuel
There are usually two idle adjustments.. one is the speed screw and one is an air:fuel mixture screw. Idle requires a rich mixture.. lots of fuel and not much air. When you get it perfect, idle speed will be low but the engine will never die on you..
Get the bike good and hot and then adjust the speed screw to get the lowest idle speed possible. Then play with the air screw until idle speed rises a little. Lower the speed again with the speed screw... then play with the air screw again and listen for the engine to speed up a little.. Lower it again with the speed screw.
take it for a ride and see if it dies when you come to a stop or if idle is too high for comfort.. if it is, repeat the adjustment. It's important to adjust idle speed / air:fuel mixture on a hot engine.. If you do it on a cold engine, it'll only idle good when the engine is cold.