The only tip I can give you is that three months to go from "not ever having run" to running a half marathon is not much time.  Most 12 week training plans are taking you from an established running base (where you have been consistently running about 20 mpw for a few months) and then ramping it up from there.  If you follow general running guidelines for increasing your weekly and distance mileage along with long run:weekly mileage ratios, then 12 weeks is simply not enough time to go from zero to fully prepared to run a half marathon.   Maybe you can choose an event at a later date so you will have time to build up your running base and then train properly to avoid injury.

I would not suggest running more than 10 miles in training.  If you can do 10 miles you will be able to do 13.1 on race day.  I made that mistake and ran 13 prior to race and ended up with injury.  Most people will tell you 10 miles is enough as your longest run prior to race day.

What does your current fitness regime look like ?

I wouldn`t say it`s impossible but without a base of running 3 miles a few times a week you are risking injury for over use if you jump too fast into a half training program. if you have a good strength training base and have done a lot of walking you  could try a low milage program and use a run / walk combo. But I would suggest you monitor yourself closely and stop if you get any unusual aches and pains

There have been a number of similar threads over the past few months.

Typical novice (beginner) half marathon training plans are ~12 wks long; they start with a training base that includes about 12 mi/wk with a long run of about 4 mi. See, for example:   http://www.halhigdon.com/halfmarathon/novice.htm   If you are starting from a base of no running at all, then that's potentially a problem since your projected race is Feb 14. Counting back 12 wks, you'd need to be at that baseline (12 mi/wk with a long run of 4 mi) by Nov 22. That's less than 3 wks from now. If you've been staying in good shape with some other form of aerobic exercise, you could probably do it. However, if you're out of shape and not doing any aerobic exercise now, then you'd be putting yourself at high risk of an injury either during training or during the event. Again - the half is not a distance to be taken lightly.

You'll get lots of advice, but ultimately it's you that will do the training runs, figure out what routine works for your body and fitness level, and push yourself through training and through race day.   Don't let the half be your first race - look for a 5K nearby within the next month, following that up the second month with another 5K or possibly 10K.   If you run slow, or run and walk toward the end, don't worry about it.   It's all about getting started, not getting discouraged along the journey and pushing yourself that much further each time.  Increase in the beginning in 1/2 mile increments each week, then 1 mile increments in the last few weeks to reach a 10 mile training run for the half.  This will give you confidence to do your best when the big day comes.

When you say first time runner - is that you never run or is that you run on occasion?  I think it's possible, but you'll spend a lot of time training.  It is not something I would recommend you do, but if you're like me and have to set a high enough goal to get your butt off the couch then go for it!

You can start doing split intervals - run in the morning, lunch time, and evening.  you can start slow - 1 mile for each run - and the slowly increase the mileage and time running.  Split training has many of the same benefits of doing 1 long run.  Your muscles may not have recovered completely from the previous runs, so don't push yourself hard.

At one point during my training I was (and probably will next week) be putting in 10 miles a day (at least) - 4 mi morning, 2 miles for lunch, 4 miles in the evening - that's 10 miles in one day.

If you have never been a runner before, this is definitely not enough time to properly train to run a half-marathon.  I'm not saying it's not possible, but the chances of doing it without injury are slim to none.

However, if you are a reasonably fit person with no health problems, you can definitely finish.  The first half I did, I walked it with my sister.  (She talked me into it, I had no desire to participate.)  We finished in 3:17, which isn't great, but it's a respectable time.  I was very sore for the next week, but I finished, and it got me hooked on running!

The 2nd one I did, my longest run before hand was 3 miles (I was still a total newbie to running, I didn't know about training obviously ), had to walk about half of the race, but I took about 45 minutes off my time...again, very very sore for a week or so.

Long story short, as long as you don't try to run the whole thing or push yourself too hard, you can finish it.  In the future, if you want to really train for and run a half, follow the 10% rule (that Mary talked about in an earlier post).  Proper training for a half-marathon takes months...