First time working as a contractor, what are important informations and dates I should know about.

Hello, I am working as a contractor for the first time and has signed a W-9 and confirmed that I will receive a 1099 report next year for annual tax filling.

 

I was wondering what quarterly taxes are and how/why do I need to do them. How often do I need to do them(as in the months I need to submit them in)?

 

What forms will I need to use for quarterly taxes, and if there are any other information I need to know as a contractor(as in do I count as a business and does California has specific laws for contractors).

 

Lastly, since I work remotely, is there any way to offset my finances if I use my own equipment for work? 

 

Thanks!