Meditation and reiki are complementary modes that enhance one's reiki practice. Not only are they beneficial to practitioners but also to those receiving reiki.
As a reiki master I find regular meditation relieves stress and creates a sense of calm. Meditation in the evening when one cannot sleep is particularly useful. There are so many apps for meditation now and often using one for 10 minutes and focussing on your breathing helps calm you and allows your mind to rest so you can return to sleep. As someone who has tried numerous sleep remedies from Rescue remedy, valerian, warm milk and gentle exercise. I actually find meditation really does help when you are awake at 3am.