1) I used to have a cheap ball machine (little prince I think) .... any who I made a platform out of PVC that I could assemble / disassemble that would shoot serve like balls at me.
2) Anytime I see someone practicing their serve I ask to return them ... I help them pick up balls so it is a win-win.
3) I have this one friend who does not really like to play sets against me since it is not competitive ... but he loves to work on his serve & volley. When I need some time returning I set up a practice date with him.
"You should be playing linebacker, not singles."