Coloring your hair can be expensive! And keeping that color for as long as possible is always a top priority. To keep color long-lasting, use products without sulfates, use warm (not hot) water, and try to wash every other day (or longer) if you can. The trio of products that have recently been keeping my demi-permanent hair color going strong are from the Paul Mitchell Ultimate Color Repair line.
I’m a big fan of Paul Mitchell hair products, which always have been, and continue to be, cruelty free. The Ultimate Color Repair line is perfect for colored hair. It’s gentle, and the three products in the line gently cleanse, condition and protect without sulfates or harsh chemicals. 
They are actually made with quinoa (a grain that’s not just for eating anymore!) and other natural botanicals. The quinoa has a high protein content that helps to lock in hair color and repair strands from within.
The shampoo contains sugar cane and lemon peel extracts add glossy shine and manageability, while powerful antioxidants help prevent damage. The conditioner adds shea butter, jojoba and soybean oil without weighing down hair. And, the Ultimate Color Repair Triple Rescue leave-in treatment protects against heat damage and has UV protection to avoid color fade.
All products are cruelty-free, vegan, sulfate-free and paraben-free.
Ok, definitely trying these! Though, I am a fan of my current combo Nexxus Color Assure.