Some tips I thought of as I was reading your post. As far as pulling off the diapers, if I put pants or shorts on over the diapers my tots seem to not pull them off.
I have to keep everything high up (the stuff I know they are after) like pens, crayons, cereal, cookies. I had to reaarange my cupboards.
Toby is constantly dragging chairs around the kitchen to get into stuff. I give him a firm no and redirect him to another area.
Be careful, my three year old literally broke his arm from climbing on the countertop, standing up fully, then falling to the floor.
We have no gates but have knob guards so they can't get into other rooms, but my kitchen and livingroom is all open.
It gets crazy, it's exhausting. I have no help and my mom is 2000 miles away. I will homeschool my other oldest three this fall. Pray for me.
Tip: I joined a gym with a nursery and that gives me an hour and a half to let them play and I let out some stress through exercise. love it! What a gift to myself.