I made my frame using three offcuts from a scrap piece of chipboard. It is multipurpose and serves (a) to hold the paper sheets and (b) to act as a stand for the clamp later on. The frame is sized to accommodate A5 paper, but you could modify it to suit A4 or A6, as the basic principles are the same.
The clamp serves to clamp the block of sheets together while they are glued. I just got some offcuts of 2" x 1" and sawed them to size, also suitable for A5 paper.
Clamping is achieved by two hefty bolts and wingnuts. Notice in the picture that one side of the clamp has an additional piece attached. This is an abutment against which the block of paper sheets is squared. The abutment is fixed only to one of the clamp sides! It just slides over the other side.
Spacers are needed in order to raise the clamp slightly above the work surface. I had a length of aluminium flat strip handy, so I cut spacers from that. You might prefer to glue additional spacing blocks directly on to the clamp.
Do not use your only iron, or your mum's, or anyone else's if they expect it back in one piece, ready for normal domestic use. As the sole plate will inevitably get some hot melt glue on it sooner or later, you never want to use the iron again for actual ironing. However, irons are dirt cheap nowadays, literally only a few dollars or pounds. I set the temperature selection dial on mine to "Silk", but you will have to experiment to find the optimum setting. The iron must be hot enough to melt the glue, but not too hot so that it singes the book cover.
Hot Melt Glue Gun
I bought the cheapest I could find. It is made by Bostik, but could be any other make you choose. It cost only a few pounds. Some guns are probably too large and unwieldy for this kind of task. I have used the one shown to bind several books already. You'll also need glue sticks, as the gun eats these voraciously. However, a pack of 12 sticks is less than two pounds, and 12 are enough to bind about six books.
You need this to cut kerfs into the spine into which strong threads are placed for added strength. Note that this use of thread has nothing to do with sewing, as in traditional bookbinding. The threads are added merely as an additional strengthening device. Make sure the kerfs are not sawn too deeply. One millimeter depth should be adequate.
The job of bookbinding is all about right angles. You will often find a trysquare useful, for instance when scoring the folds in the cover, or trimming the covers to size after glueing has been completed.
I asked the shop assistant for the strongest she had and she came up with some yarn for mending jeans. You cannot break it between your fingers. It is really strong.
This is a very dangerous tool. You need to use it with the utmost respect. Never leave it lying around on the bench or table with the knife blade jutting out. I have been using a knife like this for years for umpteen different tasks and I have got into the habit of retracting the blade immediately the cut has been made. Otherwise you may get called away to the phone, and the knife would be deadly in a child's hands. When using such a knife always make the cut away from your hands and body, so that if you slip you won't injure yourself. A blade like this can slice down to the bone in an instant. If you can't get your fingers out of the way, use a wood block or similar to press down on the item. Just never place your fingers anywhere near the blade!
This is not essential, but it does give a nice surface for the knife to cut across. Also, the grid markings assist in keeping your work and the trimming square.
When scoring the cover, don't use the Stanley knife. It is too sharp and you will almost certainly cut right through. I sacrificed one of my ordinary desert knives. However, I don't use it "blade" edge down, as one would when cutting food, but I score the card with the reverse edge, which is even more blunt.
I use 90g paper suitable for inkjet and laser printers. A ream costs under £4, far less if you buy a box of five reams. 80g paper is not thick enough, in my view. My first attempt was a total mess. I printed out the pages of my book double-sided, with the page more or less centred on the sheet. Then I had to guillotine all four sides to get the size down to A5. The trouble with this approach is that the spine side will be uneven, because of the knife action of the guillotine. The paper tends to shift ever so slightly while the knife slices through it. The answer is to reduce the number of cuts needed. If you can print double-sided so that each A4 sheet contains 4 A5 sides in total, you will experience minimum waste. However, to do this you will need to modify your page layout. As an example, take five sheets of A4 and fold them in half to make an A5 booklet. Number the pages from 1 to 20. Now look at each sheet and observe the page numbers! Starting with the innermost sheet, it has pages 10 and 11 on one side and 12 and 9 on the other. The next sheet has 8 and 13 on one side and 14 and 7 on the other. In your word processing program this is a lot of messing about to achieve the required layout.