When doing void meditation, afterwards, imagine yourself in an endless akashic sphere (complete darkness) and than imagine this darkness starts to fill up your soul from top to bottom. Don't do it for too long. Affirm that it balance your elemental energies out.
and/or
Sit outside, or lay down (if there is no too much insects) And breath in brownish energy from the ground. Feel it as a dense, hard thing. Visualize yourself as if nature would have completely take over you, and you are just a bump on the ground, you are that heavy, dense, solid ground. Now affirm that it has balanced your earth element out. Do maximum 5 breaths, when you are breathing that energy from the ground.
The first one is safer. The second one if you are at least experienced with some workings.