I've gone freelance. I need advice please

First some background. I work as an Audio Visual Production specialist. Basically a corporate show roadie. I worked for an AV Production/Rental house for 20 yrs. We had our own company-employed crews of highly skilled technicians doing shows all over the US. In the last 5-6 years the industry has evolved to where the AV houses have minimal staffs and hire freelance technicians for shows. Many of my former co-workers started doing freelance work after they were fired or quit my former company and were making more money freelance and were much happier. I've now done the same.

I've been a wage slave for many many years. This being an Independent Contractor thing is completely new to me. I applied for an EIN and registered my name as my trade name in my state (most local companies require that). I'm keeping meticulous track of my expenses since I was fired the middle of last month and have already gotten some jobs with prospects for many more.

I need advice as to what is tax deductible now that I'm a freelance Audio Visual specialist?

How do I calculate my quarterly tax payments (I already pay quarterlies on a small inheritance from my grandmother, bless her).

Basically can anyone here point me to any relevant tax documents so I'll have an idea what is and isn't deductible? Also if anyone has advice on computer programs or any bookkeeping tips that will help, I'd appreciate it.

Thanks y'all!

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