Split ends are due to excessive mechanical stress, heat, dryness, pollution, other envirnomental factors like sunlight etc So don't do any hair straightening etc. Don't blow too much hot air for drying. If proper intake of nutritional food is not there hair becomes dry,  dull and rough. You can use any good sulfate free shampoo and conditioner. And you can use leavon serums to make it smooth. Take at least alternate head bath. Use wide toothed coomb. Wash coomb weekly once. Cover with scarf/dupatta while going outside as dust and sunlight c