First you can buy any number of v expensive devices to do the job but let's assume
DIY. Get a spring carabiner, tape or clamp it to a short pole long enough to reach the
motor which somehow you've loosened from the
tender without climbing down to it. Tie a line to the carabiner, reach down and tap the spring of the carabiner against the motor handle. There you go. Now to
lift you might need a
winch on a
boat davit. a small hand-winding
boat trailer winch with that line to the carabiner (use 6 mm dyneema) over the roller or through the pulley on the davit will get you there. I have a flat bar on the sugar scoop at the stern. Once I've lifted, it's a simple matter to attach the OM to it. I use a padlock through the holes in the handles of the motor clamps to secure it. Do the same on the
tender.