You can "Follow" the Colleague site so it appears for you on your Sites tab in your Office 365 email.  

1.  Go to and log in with your Lesley username and password.

2.  You will see a Follow option in the upper right-hand corner of the screen.  Click on this option to have the site listed in your Sites tab.

3.  Now, if you are in your email and would like to go to the Colleague site, click on Sites.  Choose the Colleague site from the sites that come up.