Scotteq had some great advice. Just to add on a little bit to his....like he said, don't wrap your thumb around the neck. That's bad habit. The way I was taught was to keep your thumb behind your middle finger as much as possible. Also, use one finger for each fret (only use index finger on first fret, middle on 2nd fret, ring on third, pinky on fourth), and move your hand only when neccessary. Learn to jump strings so your fretting hand stays as close to the same place as possible. Helps prevent fatigue from having to move your arm all over the neck.
Also, when it comes to where you hold your bass, sit down and adjust the strap so it's in the same position sitting and standing. If it's really that uncomfortable, you can move it down a little bit, but you don't want it to be too low. Otherwise your fretting hand/wrist can potentially get carpal tunnel syndrom. Don't set it so the bass is down by your knees like all the "rock stars" on tv. It's horrible positioning, and will only hurt your playing.
Practice your scales as much as possible. If you have access to music, I highly recommend learning to read it. Don't know what your intentions are, but it can only help you to learn how to read the music and play along.
Learn to use all four fingers. Especially on the fretting hand. I've seen too many people try to play with only their index and middle fingers, and they end up either wearing themselves out, or just sounding very bad cause they can't keep up to faster songs. Also, learning to use all four fingers on your picking hand (or at least three) helps one play much faster rhythms. At least learn to use middle and index fingers for sure. It's extraordinarily difficult to play with just your index finger. Try to avoid using a pick too. You can if that's what you want, but learn to use fingers first.
As for those saying/thinking is a boring instrument, or guitar rejects only, save it. I've played both guitar and bass for 5 years (as well as drums for 8), and bass has always been my favorite. It may not be as "famous" as guitar, or as good as a lead or solo instrument, there is nothing saying it can't be. There are many bassists out there (Victor Wooten, Stu Hamm, Jaco Pastorius, etc.) that could outplay most of the guitarists out there any day of the week. Plus, bass is an extremely important instrument. Listen to a song with the bass playing, then listen to the same song without the bass. You'll notice that it just seems to be lacking, and doesn't sound nearly as powerful.
Bass can be a blast to play. It can also be kinda boring. Just depends on what your playing. But if you keep working on it, and practice as much as possible, you get better, and can play more interesting parts. Then you can start adding onto the more simple parts to make them more interesting. I personally love bass more than any other instrument, and if I had to chose one to play exclusively for the rest of my life, bass is my choice. Others may not agree with that, but it's how I feel.
Sorry for the long entry. Just trying to help.
I had to.....
