When choosing a type of wood, consider what materials to use to achieve your desired finished product: the age of the material and the tone of the wood. Do you want it to look young and fresh, or older with some distressing and individual character? Do you want it to be natural or stained a richer color?
Decide what kind of bench you want, and draw a template for the pieces of the bench to include legs, horizontal support and a seat. Depending on your design, your bench legs may have to be cut an angle, so make sure to take that into consideration and measure properly.
Wood doesn't always come to you cut symmetrically, so if you prefer each piece of your bench to have identical proportions, you can run your individual pieces through a planer, which will smooth them down and make them square and flat. Again, it is all about the look you're trying to achieve.
This is easiest if you construct a jig that will allow you to repeat the steps multiple times without having to re-measure and re-cut every time. The jig will guide the router and create uniform cuts. There are several different types of joints to connect your legs. One option is a lap joint; set the router accordingly for making those types of cuts. Install the legs to the horizontal seat support on both sides with screws. Attach two 2" x 6" boards to the top of your bench with screws to make the bench seat.
When it comes to distressing wood, this is one of the few times where abuse is a good thing. Creating a naturally distressed look can be achieved using various techniques — such as striking the bench with a hammer, sanding, scratching it up or simply banging it around a bit. One common technique is to use a metal chain to strike and mar the wood surface. The chain technique helps give a naturally irregular pattern.
Again, on pieces with the distressed look, the stain doesn't have to be perfectly applied. As long as it is completely covered, the piece will look natural even if it is darker in some places.