are you sure that the person who sold it to you is legitimate? I don't know the specifics of Canada, but the possession of over 26g of ephedrine in the US is a misdemeanor that carries an extremely large fine due to it's use in the manufacturing methamphetamine. The DEA has been known to watch and pursue large purchases in Canada and Mexico as well, which makes me question the legitimacy of that much ephedrine.
If you do in fact have the real stuff, then congratulations. You can get a good set of electronic scales and start capping the stuff out, or possibly dosing it out on wax paper in a fashion similar to B.C. headache powder. If you drink some electrolyte drink such as Gatorade or Powerade prior to your workout, you could weigh it out and dissolve it in the water you make your drink mix in. For example, if you wanted to take 30mg prior to workout and you usually drink 8oz of gatorade, you could take a 1 gallon pitcher and add 500mg of ephedrine in with it. Ephedrine always makes me sweat more than usual, so I like taking some electrolyte mix with it to replenish some of the salts I am sweating out.