"Go to it" is an expression commonly used to encourage someone to begin a task or activity with enthusiasm and diligence. However, there are several other synonyms that can be used to convey the same or similar meaning.
Some of these synonyms include "start", "commence", "embark on", "begin", "launch", "undertake", "initiate", "set out", "take the plunge", "dive in", "get cracking", and "take the bull by the horns". Each of these expressions suggests taking action and beginning a task with a sense of purpose and determination. So, whether you're starting a new project or tackling a difficult task, there are plenty of ways to say "go to it" and get started.