Ok, here I go...
Meditation is being in the now. You can find any position you want that is comfortable, but is best to find one where you wont fall asleep. When meditating you want to first clear your mind of the clutter. Taking the images of the day or week that pop into your head and either visually putting them in a garbage can, or some other visual technique that involes removing them from your head. Now, there are many different methods to meditation and reasons to meditate. To start with I suggest concentrating on the word "relax". Focus on the word, repeat the word in your head until it becomes so. You can even picture images that give you a sense of calm relaxation. You will get better at it as time goes on and can either focus on anything you need clarity on, or attempt to think of nothing at all.
Grounding is taking your energy and giving it back to the earth while bringing in new energies from her. One technique is to stand outside and imagine your toes as roots, climbing further and further into the earth. You then imagine and feel your energy flowing down from the top of your head into the earth, with each breath in following that, imagine "clean" energy flowing back up through you.
Elements can be found by your birthday, however not everyone has an attraction to the element they are told to have. One way to find it is to meditate "in" the elements. Eg: Meditate in water ( bath, shower, river ), in the sun for fire, in a park for Earth and well, wind is obvious and a bit tricky depending on location and time of year.
As far as practicing...practice these. If you are just starting out, practicing spells before learning how they work, why they work and what you're doing to make them work is going to get you absolutely no where unless you happen to get lucky.
You also will need to learn energy flow/control, tools, days, moon phases, colors, tools and shielding. Each of these, while not always used later down the road, are helpful to the beginner. The shielding and energy portions being of the most impoartant off the bat. The rest are tools you use in spell work to amplify them at first, and either impliment them in normal casting, or reject them years down the road. Again, if your just starting out, theres no need to start attempting to cast right off the bar. It will only drive you nuts.