The cost is low:
1) 1/4 pint sample paint can $3.99 (used three different cans)
2) Miniwax dark walnut 1/4 pint can $4.99
3) Pack of dollar store paint brushes $1.25
3) Sand paper $1.59 for 3 sheets
Total for all four chairs about $20 ... And I used three different colours.
Step 2: Tools
Sanding Block with 60 grit paper;
Draw knife (optional);
IKEA tool for chairs (if you still have it...... I have mine 8 years later..... Don't ask);
Screw driver and bits;
Miniwax Dark Walnut Stain;
Step 3: Prepare Chair
1) Disassemble chair;
2) Use rasp file to damage edges, rasp in the same direction on each length of wood, the file can even be used to dent the wood;
3) Use hammer to lightly dent chair, this will prevent the dented part from being sanded and gives it some character and contrast;
4) Use saw to cut fake looking rough sawn wood blade marks;
5) Use draw knife to trim edges;
6) Sand the parts once you've made all of your defining characteristics to the wood;
7) Reassemble chair, I recommend with carpenters glue.
The above instructions are simple because the tasks are simple. The most difficult part is to envision which parts of the chair you want the character of the distressed wood to show. My reasoning for marking the wood where I do is as follows:
1) Rasp file the edges of the wood all in the same direction (45 degrees) to the edge. This gives the illusion that the wood was rough sawn;
2) Denting or "slapping" the chair with the rasp file before sanding will indent the black from the chair into the wood and will give a worm wood illusion;
3) Denting the wood before sanding with a hammer gives the illusion of hard use and abuse such as buttons from jeans on the seat;
4) Cutting saw marks gives the look of a piece of wood that was damaged due to the blade cutting to deep from the previous cut, again emulating rough sawn wood;
5) Using the draw knife or any sharp blade to cut some of the corners of the wood is a pre step to sanding to give the feel of localized wear due to friction.
6) Finally a note on sanding sand as you wish to a depth that brings out the character of the flaws you have put on the wood but not to completely remove them or make them seem dull.
7) Wipe down with paper towel to remove excess dust.
If this seems all confusing and not explicit is because the way you distress the wood will play on its character it is subjective.