I would I.M. it if I were you. I've I.V.'d it plenty of times, but it's hard to enjoy because of how fucked up you are, plus the hole from it only lasts like 15 minutes.
with I.m. you get a very solid and consistent k-hole for 45 m in to 1 hour. it all depends on what you're hoping to achieve. if you want a full on khole you need a higher dose, for a less intense more functional high you should do less. with no tolerance these are the doses I would do if I were you.
sub khole:
I.M. = 30-50mg.
I.V. = 20-40mg
khole:
I.M.=60- 110mg
I.V.=60-80mg
you want to dose high if you are trying to hole, you can go even higher than you think you'll need because it's easier to do to little but not be fully submerged than it is to do to much. In my experience there's a certain dose where if you go over it it won't make much of a difference in the trip (kind of like a chemical governer/safe guard) so if you are prepared for a completely non functioning out of body experience and have cleared your calendar for at least 2 hours (after the hole you're still going to be fucked up and people will hear it in your voice) then it's usually ok to dose a little higher than necessary to make sure you hit the mark and aren't underwhelmed.
for your first dose you should try to familiarize yourself with the effects, so I would try a sub khole dose the first time you do it, then be sure to wait atleast a day before attempting a hole, because redosing on k can be quite ineffective.
and I would suggest only i.v.ing if you are experienced with k. I've gone on entire drives around my town (my friend driving of course) before opening my eyes and realizing we're still parked in the driveway. complete out of body experiences are par for the course with this drug, and while your soul might be elsewhere your body is still where you left it and it is quite vulnerable when vacant, so make sure you have a relatively sober sitter to house sit your body while your on vacation.