Pattern for trombone slide cover

[nenesewing]

I need a pattern for a trombone slide cover for my grandson's trombone. He is in a marching band in middle school

[westbrook]

if you can't borrow one to trace out... lay instrument down on a table.. trace around the it. Then measure around the widest part.. add a few inches for ease both length and width.

I would make a casing at the end to run a ribbon to tie closed.

what is the fabric you are going to use?

I was thinking about my Sons Sax, I think he just had a case.