Fear not, for the title is not intended to address you in a manner that is remotely as aggressive or vulgar as it might initially appear. The common street parlance of today's "Broken Britain" could very well lead you to imagine that the author is being so ill-mannered as to suggest that you should stick 'it' into a place that, while undisclosed, is rather heavily implied to be an orifice that is located about your very person. However, you can rest assured that PK Munroe (not to be confused with the legendary bebop jazz-tuba virtuoso CK Munroe) is altogether less of a bad egg than to intend such connotations. If you're picturing him as the type who might like to loiter about bus stops (yelling "I is da PK, innit, so go swivel!" at policemen and hollering "Suckle on my smelly dipstick!" at members of the elderly community), then you've really misunderstood. Shame on you for assuming that anyone who chooses to be addressed by their initials must necessarily be an uncouth young teen, who likes to wear his jeans around his ankles. No, far from being an expression of abuse, the title is actually a rather practical and functional depiction of what it is possible to do with the content of the book.
I particularly like the stickers that are intended to resemble those typically found in real life upon DVDs, books and packaged foods. The sticker "Caution- may feature actors from Friends" alone merits a mischievous trip to HMV. Also, that which displays "not suitable for adults" is positively crying out for a place on any Harry Potter book of your choosing. Particularly impressive is the marvellous array of stickers for use on public transport (specifically styled upon the look of underground signs, I believe, but still perfectly suitable for use outside of London). "Please sit up straight", "Be wary of other passengers", "No shaving" and "We apologise for your journey today" are just a few of the gems that are set out in (seemingly) authentically officious type-face.
So, while the contents are more than humorous enough for a flick through to be provisive (not technically a word, as I just learned from the dictionary, but I think I'll "stick" with it) of entertainment, far better to use them for some proper acts of subversion. Okay, it may not bring down the capitalist machine outright (nor even necessarily the government). However, you can have plenty of fun spreading them around and taking photographs (which will no doubt find their way onto Facebook). Just be careful that you don't get caught, or you may find yourself to be in a rather "sticky" situation- in more ways than one!