Class II equipment is not galvanically connected to earth thru the mains plug, hence you can't really measure the leakage current.
To measure leakage current of Class I equipment is a little tricky without official VDE 701/702 tester, because you have to measure AC current, because even if the mains section of the equipment is galvanically isolated from ground, it could still be capacitive coupled to earth.
One simple way to measure the current is with (a self made) custom extention mains cable. Simply cut the earth wire in the middle of the cable and attach two banana plugs to it. You can connect the plugs to a Multimeter in AC current mode. In that way you can measure the leakage current while you operate the equipment.
But be carefull! If the fuse of the multimeter is blown during the test, your equipment will not be connected to earth anymore!
Sorry for my drawing skills: