First thing you need to make sure you are doing is looking outside, if you are looking inside at the instruments to much, you will find yourself behind the airplane. Second thing i recommend is before you start the maneuver, trim the airplane for level hands off flight at your training cruise speed, with the power set. once you start the turn to which ever direction add a small amount of power, 200 rpm extra works well. Get the airplane established in the turn and look outside 95% of the time. When you are looking outside note were the horizon is crossing some point in you line of sight, find a bolt, anything really, some sort of reference on the plane where the horizon is going through. This is what you use to get your pitch information, if the horizon moves about that point you are descending, if the horizon goes below this point you are climbing
And every once in a while scan the instruments to check that everything is still were it should be, airspeed, alt, bank angle, then look back outside
Hope this helps