Estimating quarterly payment for growing business

Hello, 

I started working full-time as a contractor on 1099 earlier this year. It is my only source of income. I just registered as a sole-proprietor LLC and will be filing my first quarterly taxes in September. 

 

Since it is a new business my income is growing quite a bit from one quarter to another. Is there a recommendation on how to estimate my income and tax payments? Will I be penalized if I over- or under-estimate my revenue?

 

Best, 

Coumba