1. Start taking pride in what you do. This isn't just work, but everything. You'll slowly start becoming someone (at work) who doesn't want to demo something "meh" because you'll be embarrassed. If you take pride in your work, everyone else will too, because it'll be good.
2. Realize that what you do isn't for the company; it's for your fellow teammates. They depend on you. If you are late with your work, produce shoddy work, etc. then they can't get their stuff done. They miss time away from their family because they are cleaning up after you or working around your short-comings. You do your best to help them, and in-turn they'll do the same for you.
Both of these will apply to any job you have and any position. Anyway, a strong work ethic is a symptom, not a solution. Do the above and the two things you wanted will fall into place.
The only time the above can be tricky is if you have one of those "thankless" jobs. These are almost always behind-the-scenes people who make everyone else's job possible, but people rarely think about them (think janitors and IT). With those jobs it really pays to be a strong self-motivator and work for a company where those jobs are recognized for the contributions they provide.