You can create a cocoon around your body. This cocoon can give your body a few benefits or drawbacks, depending on your perspective. If you stay in the cocoon for less than an hour, all it will do is slowly heal you of any injuries and cure you of any disease. But stay there longer than an hour, and your appearance will start to be altered. It will optimise the body's natural systems, and if you have any other abilities, it will slowly transform your body to better reflect and utilise them.
An example is that if you have pyrokinetic power, your body will start to turn red and perpetually be hot, maybe even having flames instead of hair. This will result in your pyrokinetic power growing stronger, either in potency or control.