This youtuber explains how to bake lightmaps... Textures is a very similar process
https://www.youtube.com/watch?v=N5LcTTywUVs
The key points.. I will do a proper write up later.
Tick "bake rendermaps" in your Redshift Rop.
Ensure the object you're baking is specified in both the Rendermap & Objects tabs
The baker will just bake whatever it is given - so for noise/triplanars, you might want to make a new material with just that node pulled in, using a material merge. Or you might want to pull in the whole diffuse colour etc.
For bumps/float values, I use a "Color maker" node as an "out" null.. Nulls don't seem to behave. (could be wrong on this)
oh - and make sure in the IPR tab of the rop, IPR Progressive Rendering is turned OFF.
oh oh - remember to put the objects and/or lights you might want to be baking into the usual objects bit of the ROP!