Singlehanded mast up
I'm on my 3rd C22 which I single hand and trailer and also have a C25. Have a crutch or "Mast up to raise the mast from the stern pulpit to get leverage started. Use a "A Frame" that fits from the forward shroud to the bow fittings (to eleminate sway and act as a gin pole) attach the jib halyard and a block and tackle (mainsheet, boom vang, life sling tackle, etc) or trailer winch strap to the top of the A Frame. If you use the block and tackle, fix it to the deckplate for the jib tack and lead the line to a winch. Take the slack up on the jib halyard till the A Frame is raised at an angle and then cleat off the jib halyard securly. Now use the trailer or boat winch to raise the mast. Tips: if you use the trailer winch, be sure to tie or chain bow of the boat to the trailer while the trailer strap is disconnected. If you use the block and tackle, be sure your backstay is coiled loosely in the cockpit, so it doesn't hang. Also, use the reverse for lowering the mast and leave the setup attached for the next time you need to raise the mast. Saves on setup time. By using the A frame and winches you will not get sway and counterforce on your stepping pin, won't hurt your back and won't need extra crew and can stop the operation at any time to unsnag anything that gets snagged. The more you trailer and do this manuever, the easier it will seem. Good Luck