Cannot see much mention of the word "attitude" here!
When I teach steep turns I firstly demonstrate the a/c in the turn (45 degrees bank say) - all I want the student to do at this stage is look at the attitude (I emphasise that I am responsible for lookout at this stage and that all I want him to do is note the attitude!) and make a mental note of it. I then ask him to take control and maintain the current attitude (whilst I still do the lookout), having previously commented on the back pressure required to maintain the attitude. (All this presuposes that the a/c is in a perfect 45 degree bank turn - constant height, on target speed, power set, bank angle 45 degrees and in balance).
I then teach rolling out and then how to enter the turn.
A common fault on entry is to look into the turn whilst rolling in. If you do so you be unlikely to notice any inadvertant change of attitude (nose up or down) as you increase the bank angle. The lookout is done BEFORE entry and then (assuming all is clear) look ahead roll in using aileron to bank, back pressure to maintain attitude and rudder to balance at the same time increasing power - you will NOT need full power for a 45 degree bank turn in the typical light a/c - certainly not a Warrior - usually an extra 150-200 rpm will suffice. When you have established the turn then start the "Lookout/Attitude/Instrument" scan.
My best advice is to go and find a good flying instructor who knows how to teach Steep Turns but that said a couple of tips:-
1. Sit in the turn for that long that it feels unusual to be flying straight! That said if the turn starts to develop into a spiral then recover to straight flight and start again! (Also it's a good idea to have an "anchor" point when practising - some easy recognisable geographical feature which will maintain your orientation after the turn is complete. Doing steep turns on a day when the upper winds are strong can be an easy way to get lost as you are drifting whilst turning etc!
2. If you start to lose a little bit of height just reduce the bank angle a few degrees (it's cheating a bit but works a treat!) as well as changing the pitch attitude. Then reestablish the bank angle when level flight has been restored.
When you have perfected the 45 degree turn then you can move onto 60 degrees bank. Also remember that in side by side seating a/c the picture will look different in left and right turns because of the offset seating.
Be aware of the a/c limitations - many light a/c require to be in the Utility Category for Steep Turns - this means a lower max weight and different cg limts and NO rear seat passengers/baggage.
Hope this helps