Plans= What you want to do for normally the next 5-10 moves.
Tip 1: The first thing you ask when your opponent makes a move is what is their threat/plan.
Tip 2: If they have a threat/plan stop it. A way to stop a plan is to sometimes close the side they are attacking you on if its like both opponents are playing on different sides of the board. Sometimes they want a pawn break, stop it by controlling the square.
Tip 3: if not, then you have to create a plan. If you already have a plan, continue with it, unless you need to do the principal of 2 weaknesses. That is when the opponent has a weakness, but the defended it. You then play on the other side.
Tip 4: Create the plan by looking at the kings, pawn chains, majorities, files, and stuff like that.
Tip 5: Once you have found a plan, then you stick to it unless the opponent stopped the plan then you make a different plan.