How do I go from Charles de Gaulle terminal 2d to Levallois Perret?

12.50€ using a single RER ticket.  Take RER B train from CDG to Paris - Gare du Nord, walk/transfer to RER E Magenta station ride one stop to Haussmann St Lazare station, transfer to Transilien L train (ground level, departs from Grandes Lignes train platforms) in direction Nanterre Universite until Clichy-Levallois which is the main train station in Levallois-Perret.