Sorry , why not buy a harness, removeable, adjustable backstrap.

You really cant do it properly by your self other than may be a bit of back support but you dont necessarily need a professional either but care is needed in application i just ended up with blisters burns. I rely too heavily on it the idea is to give your muscles an idea of what they should be doing if you overuse it thrmuscles waste away

https://www.richmondrehab.com.au/blog/category/taping-for-postural-correction this u can do your self as its on your tummy though i never found it helped. Happy to offer more help advice based on ewxperience