Now it's only taken me 30 years to realise, but GO PLAY FOR AN AUDIENCE. Let me explain.
When you first start learning to play the guitar, it's pretty rough, go and hide out of earshot when you are practising. This will help the people you live with not hate you and guitars for the rest of time.
Typically you will get the right hand reasonable early on, bit longer if you are fingerpicking. There are only so many patterns you can do with 6 strings - okay, there are infinite, but you'll use only a few in most of your stuff. The left hand you'll get chords going early on too, but the left hand has to do so many different manoeuvres that you'll be "learning" that hand for the rest of time.
When you start to be able to play a whole song or two, you'll probably have really bad tempo and you'll do lots of pausing while your brain is trying to co-ordinate left hand and right hand. It's okay, it's how we learn! Eventually all that stuff going on in your "fore" brain moves into a very convenient "muscle memory" part of your brain. Convenient, because you don't actually have to think to play the stuff, it just happens. You can actually have a rudimentary conversation while playing, or after a few quiet ales wonder how on earth your hands know what to do because "it sure ain't me doing that!"
But while we are trying to push the song into muscle memory that's when we get a bit bored and tend to move onto something different. The curse of half-song playing guitarists. Don't do it! This is where audience comes in.
Unless you have a really, really, REALLY good friend who will listen to you, ie, an audience, I suggest you use a video camera as an "audience". What an audience does is force you to firstly learn the whole song by memory, but secondly, learn it to an acceptable level that won't have the audience looking for the door.
The video camera is great; you feel like you are performing for an audience - you'll probably feel anxious - but importantly you can watch yourself and see where you are getting it wrong. You can then practise the areas you struggle until they are smooth, aim to eventually post video on the internet to see what the world thinks of you ;)
The next battle, once you are comfortable playing for a camera, is finding a real audience. I recommend music shops - "test" a guitar and play your songs. Okay, nobody is _really_ listening but it still feels like an audience so you have to be able to play the songs well.
Where I'm coming from with all of this is about turning your music into that is something "about you" to something that is "about the listener". Going from being someone who entertains themselves into someone who entertains others. Playing the riff from smoke on the water with bad tempo hitting the occasional wrong note might amuse _you_ all day; people have been put in jail for trying amuse others doing the same thing.
Only by playing to an audience do you become an entertainer - which is where I think we should all be aiming. What's the point if you can't share your stuff with your fellow man? Ultimatley would anything, even if you had the entire world at your disposal, be fun if there was no-one to show it to or share it with?
Obviously the next audience is a real audience - open mike, busking, cafe gigs. That's where I'm heading - I'll let you know how it goes when I get there :)