Making a mylar jacket for a book that's missing its dust jacket or never had one.

This diagram names the parts of the jacket that will be referred to in the tutorial.
Red vertical lines indicate location of creases.

Now use bone folder to sharpen the crease. When you use a bone folder to make or sharpen a crease tilt it so that the edge which is in contact with mylar is the trailing edge.

The next crease to be made is designated  f   in diagram above.  Use your left thumbnail as a marker of the folded flap edge.

Use the fingers of your right hand to slide the flap back until the distance between your thumb nail and the edge of the flap is 2k ( twice the thickness of the book's cover). This causes the flap bulge up along the vicinity of crease e . Be sure the edges of the flap line up with the edge of the rest of the jacket.

Now use the forefinger and thumb of you left hand to firmly anchor the flap in this new position.

Place the tip of the bone folder on the flap close to your anchoring finger. Angle the bone folder at a 45 degree angle relative to the jacket.

Now slowly lower the bone folder all the way to the table surface.  Smoothly sweep the bone folder towards the top edge ( maintaining the 45 degree angle)

Now repeat the maneuver after angling the bone folder the other way and sweep the bone folder down to the bottom edge. This creates the crease f.

Red line indicates location of crease  e

Fold back the flap and inspect the two creases  e and  f. They should be parallel.

The process of making the crease  f  tended to flatten out crease  e  making them look in profile like

when what we want is for them to look more like is

f

What you have to do to remedy this is to recrease  e  but do it in such a way that you don't uncrease  f  . Here's how.  Again use your thumb as a marker placing it the small distance k ( the thickness of the cover) away from the folded flap edge on the midline. Now slide the flap until the edge touches your thumb nail. Make sure the top and bottom edges still line up. Now anchor the flap with the finger of your left hand. You can now use the thumb of your right hand to recrease  e starting at the bottom edge sliding your thumb along the crease (away from you) to the top edge. Position your thumb as you do it so that you aren't flattening crease  f.

Take the book and insert the back flap of your partially complete maylar jacket under the back cover of the book. Make sure the foredge of the back cover is snuggly up against creases e and f . Pick the book up and hold in your left hand , back cover facing you, spine uppermost.

You will identify the location of crease d  by pinching  the mylar at precisely the point where the midline intersects with the back edge of the spine. Pinch only as much of the mylar as is require to secure it. You may find it necessary to moisten your finger tips to make it easier to secure the mylar.

While continuing to hold the pinch, pull the mylar way from the book and place the book on the work surface on its front cover with the spine facing away from you. Leave the back flap inserted  under the back cover.  Place the pinch onto the working surface without removing your index finger and only removing your thumb at the very last moment. Do this so that the pinch is not lost, but now the mylar is pinched between the working surface and your right index finger.

Still holding the pinch with your right index finger use your other hand to make any adjustment necessary to line up the edges of the jacket and then anchor the jacket in this position. Now you can lift the right index finger and use your right hand to  make a gentle crease from bottom edge to the top edge.

Line up edges

Do not use the bone folder to sharpen either of the spine edge creses (c & d). Use of the bone folder slightly mars the mylar. This does not matter on fore edge creases e and f  because any marring will occur on the flaps which are inside the book. On the same subject, the pinch also mars the mylar a little but  that's unavoidable. With practice you'll improve your pinching skills and hardly notice the  little distorted area.

Pick up the book again. The partially completed jacket's crease d should line up well with the back edge of the spine. Pull the mylar snuggly over the spine and  identify where the midline and the front edge of the spine intersect. Pinch the mylar at this spot using your thumb on the spine side and your forefinger on the front cover side of the spine edge. Carefully pull the jacket away from the book putting the book down and transferring the pinch to the table as before.  Make the crease  c  exactly as you did the previous crease.

Fit the jacket snuggly around the book and you are now ready to make crease b using exactly the same pinching technique as before. After you've made crease  b use the bone folder to sharpen it.

The front cover foredge is handled precisely the same way as the back cover foredge so read back over that description before completing the jacket fitting.