Grounding, sometimes called earthing, is a foundational skill that can help you in both your everyday life and your magickal practice. At it's core, grounding is simply the act of realigning your energy with the Earth's energy, but it can be so much more than that. Grounding has been proven to reduce stress and anxiety in addition to improving focus. In terms of magick, grounding is necessary to get rid of unwanted energy and prepare yourself to draw in energy for magickal work and divination.
The easiest method of grounding is to go outside, barefoot, and physically feel the grass and dirt beneath your feet. While you are standing, imagine roots growing out from the soles of your feet releasing any unwanted energy back into the earth where it can be cleansed and transformed, then use those some roots to draw the energy you need for your work back into yourself. This can also be done by sitting on the ground and imagining roots growing from the base of the spine.
If walking barefoot sounds unappealing to you, try finding a tree and placing your hands flat against it's trunk. Rather than envisioning roots, imagine that the tree is a sponge, absorbing all the energy you no longer want or need from the palms of your hands. Once you feel clear of all that you no longer need, envision yourself as the sponge absorbing what you need for your work from the tree.
If you struggle with either of these methods, try working with the five senses instead. In psychology, this is often referred to as the 5-4-3-2-1 game. Wherever you are at in that moment name five things you can see, four things you can feel, three things you can hear, two things you can smell, and one thing you can taste. This process centers you in the present moment and helps clear your mind of everything that is not serving you in that particular moment.
You might find that one method works better for certain things than others. Working with the senses is particularly useful if you are struggling with anxiety as it gives your mind something else to focus on. Try all three and see which method works best for you then dive into your favorite elemental deck like the Awakening Tarot or the Southern Botanic Oracle!