Here are some points you can follow given below to creat a new software:

First plan what you need & problem you are solving.
Based on that write a pseudo code.
Then decide which language is better to write code which suits the problem definition and could work on required environments.
Plan how to code by deciding a coding architecture and choose a specific design pattern for coding.
Then divide the pseudo code in logical modules.
Statt versioning the software and build each module separately.

Good Luck!