For dlr physics you can use vimana software,
for rest use skytest and dlr cbts together,
at first few days your scores will be low but after the first week they rise quite high.
Preperation is the key, do all the modules at least once every day.
If you like the terrible translations of google translate and need some tactics, you can check "http://forum.airporthaber.com/forumdisplay.php?f=291".
Very good tactics to score high for the modules of dlr1.
I also believe dlr 2 is about preperation.
I would suggest you to ask questions to yourself as if you were from human resources.
Ask questions as much as possible.
Try to find solid reasons to possible questions.