I like to freak new shooters out at matches when there is a stage that seems to flow best with a start of maybe 2 or 3 shots then dump the mag and go. It really freaks them out to see that happen, but sometimes it's the best plan.
Another good mental tip, don't watch people shoot right before it's your turn, their screwups or different plans will melt into yours if you're not super tuned in and that can affect things. I prefer to watch a different squad vs my own squad on a stage.