Aquascaping simply means the way you decorate your tank.
Assuming you intend to set-up a Community Tank, or Marine Tank, use undergravel Filter and an external power filter. If cash permits, get a powerhead.

If you are using the undergravel filter, setup the filter first (of course!).  When setting-up tanks with sand or gravel, fill the tank to about ¼ full with water and gently pour the gravel into the tank spreading over the whole base. The gravel should be high at the back and side sloping to the lowest point where it is the easiest to change water. The lowest point should be 3" high. Overall height – 4-5" behind and side sloping to 3" at the lowest point. Plan for plenty of hiding spaces. Use drift wood, small broken flowerpots, stones stacked-up with holes in between, or even PVC (white) pipes (U shaped) and buried into the sand. Plant heavily, with longer plants at the back and side and large plants like the amazon plants at the centre or off-centre as the main piece. The advantage of having a thick gravel bed is the plant roots will have a better hold.

With enough resources, you can even set-up fences and have a two-height effect. For such type of setup, do not plant too heavily, as the effect will be lost.

Ensure that your fishes have at least some clearing for them to swim about, especially in front so that you can see them. Put a small bowl or dish for putting worms in, if you intend feeding them live fishes.

If you have no intention to use an undergravel filter, paint all 4 sides of the tank with a blue colour or any other dark colour.
Use a flower vase filled with gravel/sand to plant your plant. You cannot be thinking of Aquascaping if you do not intend to use any plant, gravel or sand.

Make sure of strong lighting for plants to do well.

Your Tank is now ready. DO NOT put fishes in just yet. Run the tank with the filters, etc., for at least 2 weeks. This is for the bacteria to grow. I know most of you will be putting fishes within 3 days. Be sure that you do not over-crowd them for the first 2 weeks.