For all those who have trouble understanding grounding and centering, this is how I do it, and of course it would be different with everyone. And of course you can tweak it however you want.
So what i do is after i meditate i go straight to grounding and centering. i visualize roots coming out of my root chakra, and i tunnel down from wherever i am, if i'm in my room, i tunneled into my kitchen then my basement then to the ground. i visualize a bright white quartz a little bit down, keep tunneling til my roots reach it. i then wrap the roots around the quartz really tight, then start taking the energy from it saving it right there, when ive gathered enough, i send the energy back up to my body, open each chakra and recharge them with the energy, starting from the root chakra, ending with the crown chakra. once i'm finished with the crown chakra, i let the last of the energy ball 'explode' and fill me with bright white energy. then i literally cut the roots and bond with the earth and im done (cutting with visualization) it helps me when i have a candle lit in front of me, the energy has pulsed the last 2 times ive used a lit candle. so i suggest maybe sitting with your element to aid in your grounding and centering.
hopefully this is helpful