I am a newbie to sex, and can't seem to maintain an erection during doogie style. I keep worrying it will slip out . The only position I can get off is me on top. Is this normal for most people, or does it just take some practice?

doggy off the bed, girls legs on your shoulders. There are many variations of guys on top 10 I can think of off the top of my head. My legs are so long that I have to invent my own positions so I feel your pain
lol

If you are worried it will slip out no biggie. slip outs happen!Put it back in and go again!

Also make sure the lady has her hips far back(but up in the air) and that your front thighs are touching her back of the legs. Make sure she is also not arching her back up,rather her chest and front end of her body is lower than her backside.(but if you're with a good provider she will know ALL OF THIS) Unless you are very large you can only do small thrusts,larger ones will result in it falling out. Don't worry and have fun! It does take some practice I suppose as I was not good at the doggy position when I first tried it(being a girl)

If you need more tips feel free to e-mail me

(civie) partners...  sex was under improvised conditions.  Partner was often flat or nearly so which made penitration difficult to impossible (depending on how determined we were).   Sometimes this flat position is called "lazy doggie."  It can be improved with a pillow under her hips.  Most other forms of doggie, she is on her knees or bent over an object like the end of the bed or arm of a sofa (you standing).  There are very many sex positions & variations.  One source of suggestions is the women's site "ivillage".   Also the back issues of cosmo magazine.

My suggestion is to try some new positions, even if you want or need to end in a particular one.  Just relax, enjoy sex, enjoy the intamacy with your partner...  it's about the journey as much as the destination.  

My Favorite partners...  have the attitude...  We finish what we start (I get my O) no matter what.  No matter how.  FS, BBBJ, TF, HJ...  everything leading up to it is just play time.  
Best wishes,
skb

First, practice fetching... oops, wrong doggie.

Maintaining wood is about a few things, not the least of which is hormonal levels (generally good when yound and worse as you age); fitness level and mental attention.

My guess is that the position, as you are doing it, is creating difficulties for you. Your attention goes to the problem of slipping out, trying too hard, or whatever and you loose wood. Take a moment as you get ready to start doggie and as you go... is this easy or hard?

The great thing about doggie is that it is super east and you can just GO! Worry less about her upper body position, which she can adjust to get her the right pressure, etc. You need to get her to adjust the height of her pussy and position of her legs.

I have short legs. Give me a gal with long legs and doggie can be tough. She can spread her legs more... "lean back" so that her thighs are not upright (she can lean back like more of a squat or forward more like lazy dog, but that would be hard to maintain). The thighs can be together or apart, which will affect how it feels.

I don't think you are talking about a provider, but civie.  If a provider, any good one will quickly move to reinsert you.  If civie, are you worried that she'll not let you get back in??   If your partner is consenting, then there should not be a problem getting it back in.   I agree slip outs happen, we laugh, giggle & either put it back or switch positions & put it back.  
skb

Doggie does me in....every time.

Great control in every other position, but man get me back there and control goes out the window.

As much as I love it, I often will avoid it.... It's definitely a head case thing with me.

Damn women with fine asses... I don't stand a chance.

Thanks for the replies! It sounds like I just need more practice so I can enjoy it.