I have noticed during the winter that I sometimes fail to ground to the earth as much as I should. This is partly because I find myself staying inside more often. However, that gives me a great reason to pull out my grounding crystals. I especially like to work with Apache Tears, Obsidean and Tiger Eyes to ground to the earth.
There are many more grounding stones that will serve this purpose, find the ones that resonate to you. I lay them out on a grid or lay on the floor like a snow angel and place one on my crown one by each foot and one in each hand. I place myself in a trance state by feeling my body becoming heavier and heavier as I open myself to the energy of the stones.
You may want to use some essential oils at the same time, choosing the ones that make you feel most connected, most grounded to the earth. I love rose oil but I love to use rose oil with anything. I just got done reading for a client when I was about to recommend Apache Tears but before I could she told me she had just added Apache Tears to her collection.