I often lose track of important papers; invitations, emails, orders, plans, only to be found after a mad dash and a flurry of everything flying everywhere until the thing is found. After nearly loosing an important receipt, I remembered something my sister has in her room to remember important papers: a large piece of cardboard, or that's how it looks at first, pinned to the wall. But it actually is a very cleverly thought out and cheap bulletin board.

Spur of the moment, I made one myself, and should you find a need for easily pin-able wall space on a budget, this shouldn't take more than fifteen minutes of your time to get acceptable results.

You will need:
cardboard
duct tape
some kind of box cutter
string
something to mark with
some thumbtacks
hot glue (actually it's optional but preferred)

Step 1: Start With a Piece of Cardboard

This will be your main material, so you may end up needing a lot! Alternatively, if you have a lot of wall space and/or aren't sure how big you want your board to be, take a side of a box and plan for a board half that size, like I did here.
If you find yourself running out of room later on, you can make smaller strips to add to the wall next to the original. Interior design majors, this is your permission to go nuts. The great thing about cardboard is that it's flexible in this way.

Step 2: Cut Out the Needed Amount

Basically what I did was take out a side with the box cutters and go with that, but if you have a specific size you'll want to get something to measure with and possible a triangle to make sure it's right. I couldn't find one, so I winged it.
Again, you'll want to cut out enough cardboard so that it's twice as much as you need.

Step 3: Mark Where to Cut

If you cut out two separate pieces then you can skip this step and the next one and go straight to step 5, but if you took the faster way and just cut out a big piece then you'll need this step.
Like I said, I couldn't find a measuring tape before, so I took the string and cut a piece as long as on side of the cardboard. Then I folded it in half and measured along that same side from the edge to the center and marked it. I turned it around and repeated the process with the same string, then held the string taut in between the two marks and traced along it with my pencil. If this is just for your room or you just don't care, this doesn't have to be exact.
Save that string, you can use it later!

Step 4: Cut Along the Line

Exactly what it says on the tin. Take your box cutter and go along the line as best you can. You now have two pieces as big as your expected result.

Step 5: Tape the Two Pieces Together

Take the two pieces and put them together with any graphics or dirty spots on the inside. Then take your duct tape and tape it all around the edges, one side at a time in whatever order. Duct tape is good for this because not only is it more than strong enough to keep everything together, but it tears nicely with no scissors needed, which you can't say for many different tapes!

Step 6: Add Loops to the Back

To hang them with, of course! You can use that string you saved to make loops, then secure them to the back with a square of duct tape.

Now, if you know which way you want to hang the thing you'll only need two loops, but I wanted some flexibility so I used a neat trick I saw on a picture frame once and attached three so it can be hung horizontal, sideways, or if you're really wild diagonal.

*NOTE*
Mine kept slipping off, I guess the tape wasn't strong enough. If you're finding yourself having the same problem, try covering the string partway with hot glue or another thick, strong glue.

Construction is done! Now to hang it.

Step 7: Hang the Thing.

Here's an example of how it works. This thing is so light you can hang it with your thumbtacks. Now, mine go through the two layers of cardboard by just a little, but it hasn't damaged the wall and it's far easier than jamming thumbtacks directly into the wall like I'm used to.

If yours comes out particularly well, feel free to show it! Also, if you have any questions feel free to comment and ask them.