Easy peasy, just turn of landing protection, and the bottom sensors. You can fly a couple of inches off the ground, but be careful, once you stop moving, you will lose translational lift, and the AC will contact the ground.
That's also the way you set it up for hand catches.....
The "Landing Protection" setting can be found in the following section of DJI GO:
After disabling this setting, keep in mind that your Mavic will slam into the ground if you attempt to do a full throttle stick down landing without manually slowing down before the Mavic makes it to the ground.