You'll get lots of varied advice, but the main thing is that you need a plan. One way (there are many) is to break it down into 3 questions:
1. Where are you now?
2. Where do you want to be?
3. How are you going to get there?
So first, you need an honest appraisal of your playing - some people aren't good at self criticism, and some people don't have enough ability to even judge that they have poor ability (Kruger-Dunning effect). Assuming you're ok on both these counts you need to take a long hard look at your playing.
Second, you need long term goals. Only you can know what it is that you want, but your goals should be informed by the problems you've identified with your playing.
Now third you map out how you achieve these goals, and then do it. After a while you review how things are going and revisit the plan. You can think of it as a never ending cycle: Plan -> Do -> Review
A good teacher could help you alot with all of this.
As an example, I was at an open mic a couple of years back, just hanging out and the singer in my band was doing a couple of numbers with an acoustic guitar. He finishes, walks over to me at the bar and offers me the guitar. I politely declined, because while I could play guitar fairly well at one point (as he knew) i'd really let my guitar playing decline over the previous couple of years and didn't have any guitar repertoire ready to go. So there we have step 1, I'd identified that I'd let my guitar playing whither away.
Step 2. I decided i wasn't happy with that and wanted to be able to do acoustic guitar stuff by myself.
Step 3. I wrote down every song i'd ever learnt to play on guitar, and added a load of other songs I wanted to play, and thought I could manage. I ended up with 50 songs, I broke these down into 5 sets of 10 and tried to focus on a set a day.
I did that for a while, but it wasn't working. I was getting stuck endlessly focusing on the first songs on the list and never getting to the rest, so I changed things up. I bought a pack of playing cards and wrote a song on each card. Now when I play guitar I shuffle the pack and deal out a card and play that song, I keep going 'till i'm bored, or it's time to do something else.
Edit to add; And +1 to joining a band! Most fun you can have with your clothes on.
Last edited by gavinspoon : 07-21-2013 at 08:02 PM.