I don't know if there's a right way and a wrong way really.

Without sitting in the cockpit looking at a slip ball you wont really know exactly what you need, so it's a trial and error process.

Here's what I do though...

I trim with aileron until it stops trying to commit suicide.

Next I fly it straight over myself and just relax for a moment and observe what it does. If it's crabbing it could be the wind, so I'll turn round and fly back over myself again in the opposite direction. If it still crabs the same way then it needs rudder trim. As you add rudder trim you'll need to reduce the aileron trim you added initially.

I just repeat this process over a few minutes until it appears to track straight and flies hands off.

I hope this helps.

Have you considered seeking out a club? An instructor can help with this sort of thing - it's much easier to understand seeing it rather than reading it....