You should have 3 mental checklists.
1) During your turn after opponent has played his move.
What are my candidate moves?
What happens after candidate move 1?
What happens after candidate move 2?
What happens after candidate move 3?
Which is the best move?
2) After you have decided on your move, before you play it.
Assume the move played, what could my opponent respond?
Am I sure my intended move is no blunder?
3) During opponent's turn
Is the position draw/won/lost?
How is the safety of both kings?
Who is ahead in material?
Who would win the pawn endgame?
What trades should I aim for, what trades should I avoid?
What pawn moves should I aim for, what pawn moves should I avoid?
What are the optimal squares for all my pieces and for my opponent's pieces?
Opponent moves..
- Threat? /or what does my opponent want?
- Do I have any checks, captures or tactics?
Then the hard part finding the correct positional move.
Silman’s course on strategy on here has been really helpful for me personally.
…Go ahead and share your thoughts and input!