Relaxation can be considered as the key to open up your subconscious mind. It can help a lot for keeping our mind focused and to create a charge within ourselves. 
Controlling Subconscious mind through relaxation and increasing mental strength

Relaxed state 

When we are in our relaxed state we can let the past belief systems go and create new belief systems. For this state to be created we can move to a relaxed and focused state which is also called the alpha state. This state of mind is generally perfect for programming our mind again. 

Relaxing techniques

Relaxation is very important for a human brain to function properly. These days, a person can relax through various ways. Through these we can easily get to control over our subconscious mind and increase mental strength. Firstly a person needs to be in charge of the subconscious mind and create a best possible state of mind in which any new changes can take place. Then a person needs to know to communicate with the mind. The more we get control of our subconscious mind the more we get to understand ourselves. When a person is in his subconscious mind depression and sadness grasps that person. Mental peace is disturbed within that person. We can control our mind through audio visual machines, through holotopic breathwork etc. Various ways are there to control our mind and create a better version of ourselves. Listening to songs and watching good movies can also lead our brain to function properly. Stress shouldn’t be taken too much. Due to this our brain is not able to function properly. Many of us like reading books. Reading story books can be also considered as a way to reduce stress and relax. Sleep is the most important. A minimum of eight hours sleep is required for our brain to function properly and increase our mental strength.

If you want to learn more about The Power of Your Subconscious Mind Book you can take a look this.