This topic has been covered to death... the search function will yield you a ton of results where this has been discussed at length.
When it comes to oxy, whether it have APAP in it or not, the most efficient and coincidentally the safest way to take it is orally.. It's BA is so high via the oral ROA that taking it any other way really serves no purpose. As others have said, plugging is also another option. But as far as snorting it, IV'ing it, smoking it (ridiculous), etc.. there really is no point.
Going to close this now because like I said before, this has topic has been covered at length.
The search engine is your friend.