Take pictures. Take some more pictures. And, keep taking them.
Any problems, post up pictures on a helpful forum like this.
If you're fairly proficient with computers, the next step would be to shoot in RAW mode.
Have Fun!
You actually should be shooting RAW from day 1.
If you end up getting a shot you like but the colour balance isn't right or too dark/light then just whip it into Camera RAW on Photoshop or lightroom.
Also... If you did the same thing with a jpg it wouldn't be the same. It's more realistic with a RAW file because it captures as much data as possible, where a jpg would limit you because it doesn't hold as much data.
So if you have the RAW file of a photo you like and it's too dark you can lighten it up by one or two stops and remember that the next time your in that situation you need to do it in the camera.
One more tip, you get what you pay for. Stick cheap glass on your camera and 9 times out of 10 you'll get a cheap image. If you go pro you'll thank me for saving you hundreds or even thousands.
As of mow though, you should be fine with the cheaper glass.
But if you decide to get a new lens may I suggest something like a 50mm 1.8
You'll get a taste of what pro glass is like, only it's actually a pretty cheap lens.
I got the 1.4 version for £300 but I hardly use it at 1.4
You'll also find primes are sharper than zoom lenses and have less distortion than zooms although today's zoom lenses are getting alot better.
Aswell as that... Try buy lenses that don't have a floating aperture, such as 2.8 or 3.5 try not to go for lenses that float from 3.5-5.6 for example.
Basically, lenses with floating apertures get darker as you zoom in assuming your at the widest aperture.
Sorry for rambling.
By the way, welcome to Nikon.