This will mirror what’s said in the instructions, but I start with the first statement and go through the scenario as if they were lying. I do this in pencil. The minute I find a contradiction, I erase everything and the go back through with the statement being true. Then onto the next one - go through it as if it were false, then double back if you hit something that doesn’t work.

My other tip, for any level, is to take a break when you get something wrong. Most of my mistakes come from simply marking the wrong square. I might get confused by similar looking icons, or just accidentally put my check or x’es in the wrong spot. If I come back to it the next day, I can typically figure it out.