I hope these three tips will be effective:
Stay away from negativity: Whatever it is, if it is filling your mind with negative thoughts then get rid of it quickly.
Focus more on positive aspects: In life many situations demotivates us, but we have to be strong enough to still move on with a positive energy.
Keep yourself busy: Keep doing on whatever you love as a part of your daily routine.
These are just simple tips which can be effective if you follow them.