You should plan on it requiring around 12-15 months to process your permanent residency application (you cannot even qualify for citizenship until you are a permanent resident - this is the equivalent to having a "green card" in the US.)
Your husband would sponsor you to be a permanent resident. You would have to document that your relationship is genuine and he would need to explain and document the plan on returning to Canada. Having a clear and definite date, such as you do will certainly help in doing that. He does not need to show any particular amount of income, but the CIC officer must be convinced you will not require social assistance ("welfare"). None of this sounds like an issue based upon what you have described.
There are documents you must gather up, notably: a copy of the marriage certificate, your birth certificate, a current clearance letter from the FBI - current as of the date you file the application, and a receipt of your completed medical examination (IMM 1017). Provided there are no public health issues (e.g., active TB) you cannot be denied on the basis of health. It is a paperwork intensive process that most people with straight-forward applications complete on their own, but you can engage the services of an attorney. In my experience, attorneys don't do any of the hard work because it is mostly personal information, but they will review the application and represent you.
The entire application is sent to Mississauga, ON. Your husband's sponsorship eligibility is evaluated there and once he has been approved, your application will be sent to the appropriate visa office - this recently changed, and as far as anyone can tell, it means your application is reviewed in Ottawa and then when ready for approval it is forwarded to Los Angeles, CA.
Once you have been approved, they will issue you a "Confirmation of Permanent Residency". That document has a limited validity period, during which you must present yourself at a Canadian border crossing offering immigration services. At that point your legal status in Canada will change from being a "foreign national" to being a "permanent resident". You do not need to remain in Canada at that point and it is quite common for people to "land" and then go back home to settle their affairs.
Note that as a US citizen, you will continue to be required to file US tax returns, report your foreign financial accounts each year, etc. You may continue to vote in the US in the last electoral location in which you voted as well. As a permanent resident, you will qualify for health care in Canada (and you continue to qualify for US Medicare once you become 65 years of age.)
After 1095 days living in Canada in any four year period you will be eligible to apply for Canadian citizenship. Note that you do not lose your US citizenship by doing this, but you do gain a few additional rights in Canada including the right to vote.
Good luck!
