Because the system works on concurrent users, you can create as many user profiles as you need regardless of how many licences you have.

To create a Team Leader profile you must have a permission level of at least Power User (75).

Go to the Menu option Setup > Users > User Profiles.

To create a new User Profile, click the +New User button.

For a full description of the User Profile page click here.

The main points for a Team Leader are:

Defaults & filters

The Allow change and Allowable Areas will probably be set to allow the User to change between and have access to other data lists.

Additionally, the Allow change checkboxes will probably be set which would allow the User to change between the Owners, Customer Statuses and Projects you have set in the Area.

Permissions

Authority level: Power User (50)

User type: Administrator

Login type: Regular

If you already have a Team Leader User configured how you want this User to be set up, you can duplicate that User. To do this you will need to go to the Menu, Setup > Users > User Profiles, click on the User you already have set up and select the duplicate option at the bottom of the page.