There are many many different ways to make wood stains. Everything from using coffee,tea, shoe polish and food coloring, clothing dyes, and of course going out and buying wood stains of which there are many different kinds. Oil based, water based and alcohol based. Some woods like pine sometimes will not take a good even stain because of the resin in the wood, there is however a prestain treatment for it that really helps even out the staining. One of the easiest to do is to get some denatured alcohol and some regular food coloring. Add some food coloring to the denatured alcohol and you have a stain. You can add the food coloring to water however that tends to raise the grain of the wood. You can make your own colors by adding different food coloring to the mix. You will have to try it on a scrap piece to see how dark or light it will be and adjust your stain mix accordingly. Another popular stain is a watered down water based acrylic paint. This will give you some color yet allow you to see the grain of the wood. Here again it might ( probably will ) raise the grain of the wood a bit. There are as I have mentioned at the beginning many many different types of stains out there. You will just have to play around with them until you find one you really like.
DW