Great - good start. You haven't said yet the weight of the object you're trying to cast - but a suggestion is to start with something about 3/8 oz. Now, using the instructions that came with the reel, take off the palm side plate and set 2 of the centrifugal brakes. Reinstall the sideplate and set the magnetic brake to about 8 or so. You should now have a pretty conservative, hopefully backlash free set-up for that weight of bait.
When you cast, stop the spool with your thumb at the time the bait/weight hits the water (or ground if your practicing in your yard). With an "8" setting on the magnetic brake, you will probably be sacrificing some casting distance but hopefully you will have no backlash. You can experiment with reducing the magnetic back a click at a time to get more casting distance. At the time that you start to see, during the cast, the line on the reel start to loosen up as if it's getting ready to backlash, add back in a bit more magnetic.
Adjusted properly, a dual-braking reel like your ProQualifier can literally be a "thumbs-free" reel except for stopping the spool at the end of the cast. Having said that, you should still have your thumb riding very lightly on the spool during the cast to stop the spool if your bait hits the water sooner than you expected or otherwise need to prevent a backlash. The reel CAN do most of the braking for you - but as you learn, you can also train your thumb to take over a bit if you want...
Remember that if you change the weight of the bait, you will need to readjust your spool tension knob (on the handle side) and may need to adjust your magnetic braking as well. As mentioned previously, some bulky baits that can catch the wind may require more magnetic braking. If all of a sudden a wind comes up, you may want to add some magnetic. For most of the baits that you will likely use, you will probably not need to set more than 2 of the centrifugal brakes.
Now, go fishing !
Thanks for the help. I'll try it out. I'm useing a 1/4 lure, but I think I have some 3/8 somewhere, I'll try that