Senna,
Try not to get fixated on the PAPIs, I used to make a complete hash of things when I looked at them. Now I don't have any to look at, (different airfield), I just make a partial hash of it!
The trick is to get your speed nailed on final, get it in trim & then leave the trim alone. Then play the throttle all the way down onto the ground - lots of very small adjustments.