Note: Not all "sulfate-free" shampoos are truly gentle, but as long as it doesn't contain Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES), then it's usually good enough for use.
Always use Sulphate shampoo and conditioner on raw hair because sulphates (like SLS and SLES) are powerful cleansing agents that strip the hair of its natural oils which then leaves hair feeling dehydrated, frizzy, and brittle.