The best way is to book an appointment with any registered RCMP agency, who does electronic finger prints. It's only 10 mins of job, and they will send your fingerprints to RCMP electronically the same day. According to the email that I receive from RCMP, I did my finger print test in calgary on 30th July and they send it to CIC calgary office on 31st. This happens in the cases where there is no fingerprint records on RCMP file, otherwise according to them it can take upto 120 days.
But I think, even if you have received the fingerprint request, it's not a big thing now days as in previous years. And things are moving really fast, thanks to new rules and system in place.
I believe the problem now is that CIC only have certain slots open for citizenship ceremony and even after the decision is made on our file, we still have to wait for 2-8 weeks to get oath ceremony, depending on the queue ahead of us.
Wish you good luck for your test.
Cheers