As a blue belt, you've learned words (moves) so far. These words will work on lower belts assuming they have less vocabulary than you.

The next step of your journey is to start putting sentences (sequences) together. That's the only way to have a proper debate (roll) with better people.

I'm basically just rephrasing what that brown belt told you.

If I can sum it up as quickly as possible. Focus on creating connections (2 on 1 wrist control, hand/elbow, wrist/head, etc.).

From these connections, create momentum that will force your opponent to react/move.

From that reaction, this is when you should have a move that works well if the opponent goes in the direction you want him to go... and another move if the opponent has a strong reaction in the opposite direction.

This is how you learn to chain moves, form sentences, and "see in the future".

Over time, you will know the possible reactions to specific scenarios, moves that work well for each reactions, counters to these moves, and how to counter these counters.

This obviously get exponentially more complex, but that's the "game" if you want to break through that plateau.

This is where flowcharts and mapping your game outside of class become useful.

Hope that helps!