heres how you can make a bellows for a large format camera .
while i realize that film cameras are the old way this can be used if you want to make a scanner camera a pinhole camera or even a bellows to pump air.

Step 1: Material List

to make this you will need :
1 sheet of black bristol board(sometimes called bristle board)
1 roll of black cloth hockey stick tape 1inch wide
1 ballpoint pen{if its dried up its ok so long as its stromgly made}
1 straight edge (longer than the sheet)

Step 2: Layout

first decide on the spacing you want in your bellows .
if you make it for a small camera you may want to use a 1cm spacing but this is hard to work with for a guy with big fingers like me so i chose to use one half inch.
measure very carefully all from the same end of the sheet and mark exactly on the lines of the ruler with a sharp pencil.
measure on both sides and up the middle.
then line up your straight edge on all 3 marks{if they dont line up then the measurement is off}.
when the straightedge is lined up hold it firmly and score the sheet with a ball point pen(not so deep as to cut through but to score it so it will hinge on the mark you may want to practice this on some scrap) .
if the ruler didnt move you will have a nice score paralell with the edge of the sheet congrats(now do it again until you get in as far as you want it}
in this case 12 inches

Step 3: Cut Up and Line Up

since this is just a demo bellows i elected to make a simple square one but if you want you can make a tapered one for that old fashioned look(or to reduce the size of the front lensboard which is why alot of old cameras look that way. it also allows the bellows to fold up in a more compact space)
the sheet was 22x28 inches so i started from the long edge and scored in 11 inches worth of lines cut it away then divided the sheet into 4 equal bits(7x11).
lay one side in front of you score lines up .
cut off a piece of hockey tape and slide it under the long edge of the sheet so 1/3rd of it is under the edge glue side up(keep it even)
press the sheet into the tape so it sticks well.
line up the next sheet so the lines exactly match the first one than slide it out so its covering 1/3rd from the other side of the tape.(leaving 1/3 in the middle uncovered).
cut another piece of hockey tape and cover the seam (so the tape is face to face) press it well to make the tapes stick to each other and the card.
repeat that step untill you have the four sheets joined with a 1/3 inch cloth joint in between each.( use 3/4 inch tape for small bellows and 1/4 inch spacing).
now to join them together to make a tube lay the assembly down with the score marks up fold the number one sheet and the number 4 sheet towards each other( they should lie 1/3 of an inch away from each other) slide a strip of tape glue side up under the two edges .
when its lined up press the edges into it then cover with another tape strip, press well again because all this is going to be strained around and a bad tape join may pop and ruin the whole thing.

Step 4: Folding

folding while this step is simple it takes a long time so settle in a comfy chair and get to it.
fold the nearest edge to you away from you( bend it so it creases nicely)
then turn the tube 90 degrees and fold the top edge towards you then 90 degrees fold away,90 degrees fold towards and so on.
as you can see the card wants to bend on the lines we scored earlier thats good.
when you have folded the top move to the next row below and fold it opposite of the one directly above .
repeat the pattern until you get to the bottom.
this will get hard to do with smaller bellows but go slow and dont try to rush by doing more than 1 row at a time. also if you decide to turn it over and start at the other end too make sure you keep close track of what one bends in and what 1 bends out.
now some of you are probably thinking why didnt he fold the sheets before he taped them together?... anyone? no?
well ill explain it anyway . if you fold before hand it almost never lines up accurately so you get out of alignment and the joints are under unequal strain and fail.

Step 5: Finished

and there you have it a bellows ready to be used on a camera project
this bellows will compress to about 1 inch or stretch easily to 10 and relaxes at 7 inches just glue or staple it to the front and rear standards of your camera and your good to go
total cost for this project was about 3 dollars and that will get you 2 bellows this size and enough leftover hockey tape to do 10 more at least
my next contri will be a pinhole camera made from one of those bellows and some old 8x10 photo paper boxes . then perhaps ill show how i made the replica field camera in the title pic.

any questions ? bring em!
len