You can create a new quote from either the Quotes List Screen
or Customer Details Screen > Quotes Tab
In either case use the Add New Quote button in the top right of each screen. From this point on the process is the same.
Enter the initial specifics
1. Select an Existing Company
2. Create a New Company
3. Select and Existing Contact
4. Create a New Contact
Enter any notes or details and click Submit
Once the new Quote is created it will be displayed so you can edit.