How to Create Drive Without Partition?

Follow the following Steps :

1. Right Click on My Computer and click Manage 
2. Click on Disk Management
3. Right click on your desired drive and click Shrink Volume
4. Write the size of the volume.
5. Now click on New Volume
6. Then Click Next and Give it a Name
7. Write the Letter if you want change Drive Name

And it is done, your drive is ready to use.