Best method to practice openings/best software?

Actually, in my opinion, playing the opening you learned regularly in games is the way to improve your opening knowledge. In this way, you are experiencing new ideas against your opening and also you know how to deal with the middlegame occurring after the opening. If you learned a gambit line and your opponents don't play into your gambit, I recommend you to join my team where you can practice your gambit lines in the tournaments we organize. We are going to organize tournaments after we reach 30 members so your help is been appreciated.  

I used to struggle a lot with my openings until I found this tool that analyzes past games and points out mistakes. It’s been pretty helpful in showing me where I go wrong and what to improve. Just putting it out there in case anyone else finds it useful: AIChessCoach.net.