Is this 'manual' or motor driven?
If this is 'manual', then the key to getting the awning tight is the upper sidearm, the 'TENSIONING arm'. You first unroll the awning, and the very next thing you do before raising it any more is to extend the upper sidearms as far and as tight as you can get them. It's hard to do if you are short, alone, or have small hands, and on our RV it is one of those MAN jobs. It is important that when you are pulling the thing tight, that you pull on the upper sidearm itself, not the awning roller, because otherwise you dont get it fully tight. Then you have to get the knurled nut tight before you let go. Two people are really great for that step, one to tension, and one to turn the locking nut.
Once you get the upper arms tensioned, then you can raise the lower 'SUPPORT arms' to your liking. If those numbers are on the lower 'support arms' then they are only there to tell you that both sides are the same height. Most people actually raise the lower arms to different numbers, since the incline allows rain and dew to run off more quickly.
Get the upper sidearm tight and you are all set.
Hope this helps
Rankjo