Skip step 1 if you already have an activation code that has not expired.
Use your UMBC email address to request an activation code from hereand the code will be sent to your UMBC email.
Go here to download the version of ChemDoodle that you want(ChemDoodle 2D, ChemDoodle 3D, ChemDoodle Mobile). Follow the onscreen instructions to complete the install (use the activation code from step 1 when if the installer asks for an activation code).