IMO good rudder use is what separates the casual sport flyer from the really accomplished pilot. As you progress towards aerobatics rudder use ceases to be an option and becomes a must.

Once you have learned to use the rudder, you'll be flying on windy days while the rest of the crew sit it out.
As far as easy tips, the rudder reverses just like the ailerons do when the plane is coming towards you. So to correct an unwanted heading change or reverse a bank (on a high wing plane) push the rudder in the same direction as the wing that is low.

High wing planes (like your Cessna and Avistar) will turn quite well on rudder alone, so in order to get some meaningful practice, you might consider performing most of the flight with rudder instead of ailerons.

My cross-wind landing technique is the following:
Turn into final but overturn or under turn a little so that the nose is slightly pointed into the wind. This will compensate the drift from the intended flight path because of the wind. The plane is effectively moving slightly sideways at this point - what is generally known as "crabbing".

Hold this heading (nose into wind) using the RUDDER and only use the ailerons to keep the wings level. Since highwing planes will turn on rudder application, you will have to apply OPPOSITE ailerons to keep the plane from continuing a turn into the wind.
Because the plane is flying "dirty" due to the cross controlled rudder / ailerons and because its flying "sideways", drag is much increased as compared to normal flight conditions. You must, therefore, increase power and apply a little up elevator to compensate for the increased sink.

A side benefit from learning to effectively "crab" your plane, is that it comes in handy when you come in too hot and risk overshooting the runway. By inputting cross controlled rudder / ailerons, you can quickly loose altitude, reduce speed and still make your intended landing spot.