Leave it alone. Mostly. Worms don't like to be disturbed. They will be happier of you do not turn your bin. But I found that if I don't turn the bin, I get a bunch of compacted matted bedding at the bottom of the bin that never decomposes. This needs to be broken up and brought up to the surface. So I suggest you turn your bin once about half-way between setting up the bin and harvesting. So if it takes about 6 months to get to the point of harvesting, turn the bin one time about 3 months into the process.

no. a good made worm bin should NEVER need turning.

only time you should turn your worm bin is if your having problems with air. if your having problems with air you made the bin wrong.

when i used to have a junk worm bin made out of a 5gallon bucket i had to turn it mainly because of lack of air due to the fact i piles the bucket which was a bad idea. as the worms only go to certain depths and you obviously don't want the bin to be too deep to the point the bottom gets no air and is not composting and becomes stink. the worms help aerate the bin as well by moving through it but they also need an air supply so you want your bedding loose for the most part not matted down.

when i make my bedding i use cardboard, news paper,w.e. carbon supply i got. i wet it down. fluff it up with my hands add a little old compost for the mircobes mix it it with my hands again with the carbon materials and put the food on then top with wet bedding again. never had any problems with this. i find my worms always at the surface but not crawling out it's that loose. eventually it will decompost and you can add more bedding later

I have little experience with RM plastic bins, but I would not turn. By slowly top-feeding only, the "most done" stuff is at the bottom. So the worms stay near the top 8". Anything below that should have few worms and be ready to harvest. Simply put the top 8" or so of material aside and dump the rest into a pile. The top 8" goes back in the bin and then sort or sift the pile.

Mixing would cause the worms and food to be spread

I sometimes use a pitch fork to lift and fluff the bed and get some air in. But I do not mix.

Being able to turn through all the material in the bin and see what is going on is the fun part of having a bin. I figure the most useful time to do this is about halfway through the compost time to mix in any larger materials that have not yet been enticed to decompose.