As you start to make the tack, bring the sails in; or in a jibe, let them out. This powers you through the turn.
Be sure that the slot is correct; about 12 degrees from the centreline for the jib, and 5 degrees for the main.
Rough rule of thumb- point jib at sidestays and main boom at corner of transom.
Make the turn as fast as you can without stalling the rudder.
In light airs, ease away from the tack to pick up speed before making the turn.

Good luck and happy sailing!

Edward.