Try to bear in mind that your early stuff is very likely to be terrible, and that you shouldn't let it get to you further down the line when you're rereading it and cringing. Focus on the present. If it really really bothers you, go back and redo the old stuff, but don't take a break from the main canon to do it, because interruptions in a story are a big turnoff. And regardless of what you do with the old stuff, remember that your readers probably like it as it is.
Don't be discouraged by your self-perceived inability to draw. Your skills will improve on their own as time passes. Once you start to feel comfortable with your abilities, when you reach that point where you feel like you know what you're doing, then it's time to really start pushing yourself, because that's the most likely time that you'll become complacent and your work will stagnate. Always challenge yourself.
Practice your hands. Hands are hard as hell to get right. When you read other comics, take a look at the hands and figure out what you like about the artist's hand style and what you don't. Awkward looking hands can make a drawing look very amateurish. Granted, we're all amateurs here, but you don't want it to seem that way.
Learn to love drawing. Try to find a process that makes you look forward to working on your comic. Sketch stuff on your notepad when you get bored in a meeting (good time to practice hands). Have fun. When your comic stops being fun for you, you'll start to resent it, and you'll find yourself making one or two late updates, then a few more, and eventually the comic just dies and you never update again.
Try to go a year without missing an update, and then start trying to grow your audience. If you build up a fan base and then suddenly stop updating, those folks are going to make your life miserable for a few weeks, and then they'll give up, and then the next time you get back into the comic, you'll find it even harder to get readers than the first time.
That's all I can think of right now.
