This is really simple, It's not for those who have a very weak signal, but for those who already have a TV with an internal tuner and just want to use all the available features. Also, why buy an expensive antenna or spend more time building a bigger more complex one if this little thing may be just right for you?
If you know for sure you will need a really good antenna, I would suggest this other tutorial
You don't need more than:
a balun impedance adaptor (close look below);
1m long rigid copper wire;
a stantard shoebox (if there is a standard);
some aluminum foil
a plier and some utility knives.
Oh, after the antenna is ready, you will connect it to the tuner through a RG-6 coaxial cable with F connectors, so you just might buy some of that at the hardware store too.