I like to be calm and focus on breathing as I'm getting ready. In through the nose pushing the diaphragm down then out slowly through the mouth.
Then it's all about visualizing the lift step by step.
The absolute last thing I want is anything negative to seep into my head. It's a "oh fuck this is fucking heavy" type of mindset once I pick it up or hoist it or whatever.
I have to keep that out of my head or I'll lose. So I peel it back to just "pick it up and move it till you can't no more" and it seems to work well.
That "Oh fuck this is heavy" vein that runs through my head is like a cinder block sitting in my lap. I can still do stuff and move around it but it still sits there and bugs the shit out of me, drags me down, affects my output.