Automatically updating multiple sheets to a master sheet

Say for example I already have data in the master sheet from all worksheets. When i add new data to ProjectA worksheet and run the code, it copies it underneath the previous ProjectA data in the master. Same with project B, if new data is added in its worksheet, then it copies it directly underneath the last project B data in the master sheet. I just want any new data to go in the next available row. Hope this makes sense!!