There are many methods of recovery that can help you heal and recover faster. Taking cold showers can help inflammation and heal your muscles faster. Tart cherry juice and tumeric also helps with your inflammation. A literal entire rest day is also helpful to recalibrate, and heal tissues in your body. Drinking a lot of water and hydrating to keep your body healthy is important too.
If you are working out multiple times in a day, you should at least have 2 hours of rest between each session just to prevent injury and insure your rest. Eating protein before and right after your workout is also good as well to produce and develop stronger muscles.