Go to courseware.uleth.ca and choose to login. Use your UofL username and password. The same ones that you use to access your email.
If you are unable to gain access first ensure a few things.
Ensure you actually have a Blackboard course to access. Not all instructors use Blackboard and if you have no courses utilizing Blackboard, you will be given a login error as there is nothing for you to access and as such your username is not given access to the system.
Ensure you are typing in the correct username and password. If you are unsure of your UofL username and password, please visit the password change form provided by IT.