This is done in the account that has the folder to be shared
1. Right click on the folder you want to share and choose Properties
2. Click on the Permissions tab
3. Click Add
4. Search for the user, then Addand OK
5. With the name highlighted, select an option from the Permission Level dropdown. The permissions associated with that permission level update in the Read / Write / Delete / Other sections.
6. When you are happy with the level of permissions, click OK