Sure you can! Here are the things you'll need to do:
1. Unlock your phone (if it's not already). Your old provider should offer this to you for a fee (normally $50 but it varies) or you can visit a third party store or website that will do this for you. A quick way to test compatibility is to borrow someone's Telus micro SIM and put it in your phone - if it works, you're good, if not, you'll need to unlock the phone.
2. Go to a Telus corporate store or retailer that supports Telus prepaid and get them to activate service for you. SIM cards cost $10 to buy and you can activate yourself or get a store-assisted activation.
Your other option is go on a MTM (month-to-month) plan. This is postpaid billing, but because you have your own hardware you are not bound by any terms, the plans give you more/$, and you are elgiible to receive a 10% discount on your monthly bill while you're still on MTM! If you ever wanted to upgrade your phone or leave, you're free to do so anytime. Exceptions may roll around if you get activated on the spending limit program but that's a bit more detailed. You can also migrate to MTM from prepaid later on, if you wish.