Use “junk mail” envelopes.
"Most everyone receives junk mail and a lot of time’s this junk mail includes a return envelope. Keep these and use them the next time you have to mail something."
I just read this tip on Money Saving Mom's site and thought it was a great one! Perhaps, you've already been saving your junk mail envelopes, but it was a new concept for me and I was quite excited about it!
Do you have any other frugal tips to save money?
For other frugal tips, check out Money Saving Mom's post, "10 Simple Ways to Save Money at Home."