In the name of Allah, the Most Gracious, the Most Merciful "[Prophet], recite what has been revealed to you of the Scripture; keep up the prayer: prayer restrains outrageous and unacceptable behaviour. Remembering God is greater: God knows everything you are doing."...
Whenever you are on the verge of complaining about something, pause and give thanks to Allah for all the things that are going right in your life.
Truly trusting Allah means accepting and internalising that He knows things we do not know, He has power over all things and everything belongs to Him.