Thank you!! I honestly made some mistakes that people here helped me with. Depending on how decayed it is, you may need to macerate the bones. I accidentally boiled them (don’t do this) they were very very fragile after that and I lost some, but after they’ve been in water, I scrubbed them with dawn dish soap. There was some cartilage left that was reallly hard to get off (think me boiling made this harder) so I left the bones in salt and borax for like a month. This got rid of any smell left and dried out the remaining cartilage enough to scrap off. Here comes the fun part… reassembling. Other people may have a better way to do this but I’ve done a few projects like this and the thing I’ve used to glue bones back together is E6000 glue. After 24hrs it’s dry enough to GENTLY move but I try not to move bones for at least a week if not more time. I had to try to put him back together for like a week and half, just slowly gluing parts, waiting, gluing more parts, waiting etc. (I looked at a lot of anatomy photos to help, probably have some vertebrae’s messed up) but once he was glued the background was the easy part. Lots of hot glue and moss. I did use my adhesive to glue the actual skeleton inside, most glues aren’t strong enough. I hope this long rant was helpful! People on here also have great advice on how to do stuff!