Patching and Plastering - doing knock down texture

I am fixing to do a knock down texture on a kitchen remodel and I have a couple questions.

1. should i prime the wall before I do knock down texture

2. how long should I wait before I start running my knock down blade over the texture.

Welcome to the forums Brandon

#1 - no need to prime new drywall prior to texture [unless you don't paint the texture]

#2 - it all depends - the main thing is to be uniform across the whole ceiling. The thinner the mud and/or the quicker you knock it down the less the texture will stand out. Heavier mud will give heavier texture. If unsure it would be best to practice on a scrap piece of drywall or cardboard. Weather conditions [heat,humidity] will also affect drying time.

Right there with Marksr..... If you drag your blade to early, you end up with a flat surface - to late and you end up just knocking tips off of peaks. I try to judge when the thinnest part of my texture is starting to change color to dry - then lightly (very lightly and at a great angle) start dragging my 15 inch knife over the texture. It's easy once you get the hang of it - but I would suggest playing with some scrap drywall and texture first.