Since in poker you often find out about a hand's strength after the tell has been spotted, how do you keep the connection in your brain between the actual tell and the hand itself?
Does anyone have some sort of system they focus on while playing? Memory hacks?

I think most of it comes down to getting used to thinking about it. The more you pay attention, the more it's easy to pay attention and remember the right things.

Having said that, I think taking notes on your phone is a good way to help your memory, especially for things you think are more important than most. Nobody knows whether you're taking a note or surfing the internet or texting someone, so I don't mind that. If you're taking notes on regs, you can even organize notes by their names.

Of course in poker the easiest way to remember a hand is to lose it!! (not the most recommended method though).

If you struggle with metal notes, then definitely take physical ones. I try to focus on poker both driving to and driving from a session. Sometimes with radio off if I feel a bit unfocused that day.

Since you may not know who you are playing against that day, just try to review hand histories and what you saw and what you need to look further into as you try to make sense of the actions.

I find it much more productive to think about my game going to a session and reviewing my opponents game when leaving. This may sound 'simple' (even insanely logical) but a lot of players dwell on their own missed opportunities going home and then lose some detail of the memory of opponents actions when they have 'settled down' later.

Assuming how others will play may lead you to forgetting how your play got you into the spot to begin with or lead you to false assumptions during play. Remember they were in the hand as well and 'should' be thinking about a Plan B themselves. GL