You can have one Business reported on Schedule C, with income from a 1099-Misc plus other income NOT on a 1099-Misc combined for your Total Business Income.  You don't have to 'split' the income. 

Type 'schedule c' in the Search area, then click on 'Jump to schedule c'.

Edit/Review your Business, then choose Business Income and Start/Update. 

You should get a screen asking 'if you have other income not reported on a 1099-Misc'  or 'tell us about additional income', depending which TurboTax product you are using. 

Click this link for more info on Reporting Business Income Not on 1099-Misc. 

I meant how do I split the deductions?  The software puts the 1099-c income and my non-1099 income in separate places, but i have to itemize the deductions for each.  I can't lump sum the deductions.  I work from home and have a dedicated office space, so all my office is used for both the 1099 income and non-1099 income.  

Do I total my home office deductions and gas mileage, consider what percentage my 1099 income is and what percentage my 1099 income is, then use the same percentages of the deductions for the two income categories?

My apologies -- I did not carefully read your first answer.  I will carefully re-read your first answer.  Ignore my follow-up question for now.

I have a question for you that may make this easier for you.....Is the income in question for the same business type or is it 2 different lines of work you are doing...........and is any of it W-2 employee income?   

The income in question IS for the same business type.  It is not two different businesses.  None of it is W-2 employee income.  I didn't hire anyone.  Thanks much.

Then it all goes on the same Schedule C - you don't need to divide your expenses up between the 1099 and non-1099 income.   You will list one business Schedule C and enter all of the income on that Schedule C.   There is a place to enter the income from your 1099s and then use the Other Self-Employment income category to report the income that was not on a 1099.  

You only need to divide your expenses if they are for 2 different businesses or some are personal (non-deductible).