When you first start the game do NOT go all engineer mode and try to build the ultima house from day 1. Your first house needs to serve to protect you from monsters at night, because in the game unless you have some kind of barrier, they will attack you in your sleep.

A small simple structure is ideal. Try to

-made it out of dirt or sand so that it wonn't burn down. wood looks good but it's better for fancy homes since it's not quite as accessible as dirt or sand.

-not leave a mountain behind it, unless it's literally built into the mountain. monster can fall from that mountain and if your house is'nt finished you might suffer the consequences

-keep it small at first so your not too worried about a wall missing while you try to sleep because you ran out of materials. NOT fun. Remember you can always expand later, but you need to be alive first.

-Do try to leave a hole at the top, unless you can make a torch (below). light will always be around, by moon or by sun. Know monsters cannot climb flat walls. they can climb stairs though, and the will if available. Giant spider CAN climb through walls, but the are too big to fit through a one hole gap.

Once you have your basic house then it's a good idea to take a look at the area around you. if there are at least 3 different monsters around you that means there are at least 3 monster spawners near you house. Since you don't want to be contantly fighting outside you might not want to stay in that house but only long enough to gather resources to build a new one some where else.

Now if you want to make your house more like home look around and see if you can find some wood, animals, or rocks.
Try to get enough wood for a crafting table, those are always handy. Remember 1 peice of wood froma tree makes 4 peices of wooden planks

E w w E= empty space
E w w w = wooden plank
E E E

4 wooden planks = 1 crafting table

Most animals can be killed for meat but if there is a sheep then thats special. Killing sheep can give you wool which you can then use to make a bed, if you gather enough wood too.

E E E E=empty space
W W W W=wool
w w w w=wooden planks

3 wool + 3 wooden planks = 1 bed

A be is handy because if you right click it at night you will go to sleep, and if no monsters attack you you will skip the night!
Another handy tool is a door. Monsters aren't smart enough to use a door, but hopefully you are. A door simply needs more wooden planks, 6 to be exact.

E w w E= empty space
E w w w = wooden plank
E w w

6 wooden planks = 1 wooden door

Next up, a furnace. You know those animals you killed for food? ya, they don't feed you much do they. If your food meter drops to zero you might die o.o , bad. So what you need to do is build a furnace. A furnace is a stone block with two squares if you right-click it. The top square is what you want to be burned or cooked. The bottom square is what you are buring which will usually be wood or charcoal if you can get some. To make a furnace get 8 peices of cobblestone (what comes out of stones if you break them), note this will be much faster with a pickaxe.

C C C E= empty space
C E C C = cobblestone
C C C

8 cobblestones = 1 furnace

Yay now food can be cooked. Hey remember that stone you dug out. See if you can find a stone with some black stuff on it. If you do congrats! That black stuff is charcoal, but you can't get it if you break the block with your hands. You need a pickaxe or it will just break. If you do have a pickaxe then by all means gather as much charcoal as you can get.

Now once you get charcoal make some sticks out of the wood/wooden planks.

E w E E= empty space
E w E w = wooden plank
E E E

2 wooden planks = 4 sticks

Then use the new sticks and charcoal as so-

E E c E= empty space
E E s s = stick
E E E c = charcoal

1 stck + 1 charcoal = 4 torches

Yay, the future is so much brighter! These basic objects will complete your house, unless you want to take it all up a level. In which case experiment with materials. If you go into the rocks a little you might find daimond, redstone, iron, and gold! Carefule of monsters and try to burn a few things, it becomes plenty of fun!