1. In a gradual manner
   - gradually, bit by bit 
2. Proceeding in steps
   - stepwise

1. One thing at a time
   - bit-by-bit, in small stages, piecemeal, stepwise

See also: gradual

Encyclopedia: Step by step

• supplant
• supplanter
• supplanting
• supple
• supplejack
• supplement
• supplemental
• supplementary
• supplementary angles
• supplementary benefit
• supplementation
• suppleness
• suppletion
• suppliance
• suppliant
• supplicant
• supplicate
• supplication
• supplicatory
• supplier
• supply
• supply chamber
• supply closet
• supply line
• supply officer