Marriage Sponsorship (Toronto)

My fiancée is Canadian and we are getting married next month. We will be starting the Spousal sponsorship for me to become a Permanent Residence. Currently I am here on a tourist visa. I am wondering if anyone has any advice on this topic. Should we look at hiring an attorney or would it be best to submit our papers to the government alone. Should we apply within Canada or outside. If anyone has had some experience with this any advice or knowledge would be greatly appreciated.