One of the simple tips that I give that is immediately useful to most people is a recommendation to implement high/low programming in their training.
The basic idea behind this is that if you have a day on which you have a stressful/draining session (high intensity), the next day should be an easier day (low intensity). This will enable your body to recover more easily, and help to prevent overreaching and overuse injuries.
Here are some sample ideas of what is categorised as high and low:
* Heavy weight training
* Plyometric Drills
* Hard sport practise/Competition
* Easy jogging
* Technique work
* Light weight training
* Massage and other recovery modalities