1. Wash garment inside-out in cold water using a gentle wash cycle , This will provide more protection and less direct contact of the shirt prints to other garments. This will prevent its color from fading, retaining the original fresh color tone.
2. Hang dry your clothes ,  Heat is always bad for prints! They shrink garments and t-shirts (especially cotton t-shirts) as well as damage t-shirt prints, making them crack or peel. Hanging dry your clothes the old fashion way is the best method.
3. Avoid using bleach or strong detergents, it might damage prints on a shirt making the print fades and quality of the shirt to shrink.
4. If iron is necessary , iron the shirt inside -out on the lowest setting , Never iron directly on t-shirt prints. If there is really a need to iron, lower the temperature settings of the iron, turn the t-shirt inside out and iron. Again, heat is always bad for t-shirt prints, prolonged ironing will damage the prints, causing them to peel.