I got into Set Game about a few month ago. Though not an expert by any means, I am getting better. And through trying to get better, I could not find any online resources to tips for this game. Here are some tips or ways of thinking that may help you.

First, for me, I usually get between 1 and 2 minutes. My record is 36 seconds. Although sometimes I do get into 3 and 4 minute territories.

The basic premise is all the same or all different.

I try to identify rare linking cards and work off of them. If there is only one 2, then I look for a 1 and then think what would be the only usable 3 to go with it. If it’s not there, scratch that and move on.
Look for the rare linking cards.

I see what colors are present and if there’s 3 of something right away. This is usually easy to analyze quickly.

Be methodical. Check all equal fills, all 123s, all 1s, 2s, 3s, all equal shapes. The same fills, numbers, shapes should be easy but they are sometimes left out and you usually kick yourself when you find it at the 3:30 mark.

Don’t worry about duplicate sets. Don’t bother checking your status on the side, it’s a waste of time.

Narrow down what is possible what is not possible. If there is only one card with a singular item on it, you can do a 1,2,3 with that card only – so exhaust all possibilities with that right away.

Do you have any other tips?

Links:
Set Game Official Site
Wikipedia Set (Game)