Swab testing is a laughing matter. Seriously the swabs are a joke and it is probably the least effective method of drug testing. I have been through a near countless number of saliva\swab drug tests over the years and I can count the number of resultant positives on one hand. And this is without taking any counter-active measures to obscure the result. You pretty much just need to brush your teeth and clean your mouth out real good (with a toothbrush and regular mouthwash). They make it clear that you're not supposed to drink anything up to ten minutes before the swab, so if you can just rinse out good immediately prior.
Another 'trick' I am aware of is that some people keep the swab between their teeth as opposed to against the cheek as it is supposed to be given. What you can get away with will depend on the folks (technicians) administering the test. Chances are they wont be paying close attention because they probably aren't being paid very much.
