How do I know my estimated quarterly taxes?

Hi, 

Here is an IRS link you can use for IRS federal estimated taxes:

Self-employed estimated taxes 

Within that link, you can use the IRS withholding estimator.

You can fill out the estimator, and it will determine how much you may owe, that will give you a better idea of how much to pay in estimates throughout the year. You shall pay estimates if you expect to owe at least $1,000 in taxes after credits and deductions. Also, you should pay the lesser of 90% of the tax shown on the current year tax return or 110% of the tax shown on prior year return.

Here is also a link for instructions regarding Colorado estimated taxes:

Colorado Estimated Income Tax Instructions  

Here is an article about estimated taxes, what to pay and when: Estimated Taxes: How to Determine What to Pay and When 

And more information regarding being a 1099 employee: 1099 Employee