There are two basic styles ...... the one where the bowl screws into the base and the one where the bowl is held in two 'arms' extending from the rear of the machine towards the front.
Is yours the one on the left or right?
If it is the one on the left (has arms), first lower the bowl. Then just hold the handle and lift straight up until one of the pins holding the bowl is disengaged. Then sort of rotate the bowl forward to disengage the spring lock at the back and the bowl's off. By the way, the best way to put the bowl back on the machine is to tilt the top of the bowl toward you (almost as if to pour it on yourself), set the two pins, and then tilt the bowl back to engage the rear spring lock.
If yours is the one on the right, that has the bowl that screws into the base. Turn it the same as you would a jar lid. It needs maybe 1/3 of a turn to disengage. If it seems to require too much force, you're probably using too much force to put it on in the first place. If it seems to work tight as you mix (not likely, but anything's possible) then the way is the same, but apply more force. There's really no trick to this style. As Mr Miyagi may have said to little fly .... twist on ... twist off.