There are tons of options--it really comes down to what you like the most. Look at a bunch of tank builds and decide what you think looks best, make sure you know all the basics, and then plan your build around that concept. For example, maybe you like the look of a bare-bottom tank instead of a sand bed, or maybe you want a nice deep sand bed. This can influence what kinds of livestock you keep (sand-dwelling gobies, etc), how much flow you can have, and what kind of filtration you'll be relying on. There are tons and tons of threads on that debate alone. Take your time and decide what you like, and then research how best to go about realizing your vision.