On a regular basis there are conversion bonuses, which usually require that you have auto conversion activated. To maximize accumulation of Aeroplan points:
1. Normally keep auto conversion off (you can keep you Aeroplan and Le Club Accor memberships linked).
2. When a conversion bonus is announced, turn it on in your Le Club Accor account, and keep it on until the bonus period is over.
Please note that conversion is not instantaneous, but it's still pretty fast.