One can ground simply by sitting down and envisioning roots traveling from them and into the ground. Picture and feel the negative and pent up energy in your body going into the ground.
Reason for grounding:
A lot of time our energies can build up, or we may have negative energy within us. By grounding this energy we can be more calm and steady, as well as our energy easier to focus and control. In meditating it is good to ground before hand because you can draw in much energy when meditating, as well as the built up energy and negative can mess with the effectiveness of your meditation.
Symbols to help with meditation:
It may be best for you to create a sigil with the goal to help your meditation. If you would like an example of such a sigil you can message me and I will make one and put it in photos. I would suggest however you make your own as it would be more connected to you and thus more effective.
If you have any questions about the information above or need more detail please message me and I would be happy to help.