I am crappy at making these type of things. This was done on my iPad so the picture quality is rubbish as fuck but oh well.

What I used:
-PicsArt
-polarr
-Adobe Photoshop Express

Step 1: Grab a bookmark (I used Burningbrightfire's Alaska bookmark which is the first photo) to get the correct size before selecting a background and model before darkening the bottom.

Step 2: Add your sentence, logo and little detailing; if I had to change one thing I would not use the font for the sentence clause it looks horrible.

Step 3: Add a blood brush effect type thing (so not used to doing things on PicsArt)

Step 4: Add a colouring which darkens the bookmark even more.

Step 5: Go onto polarr and add some photoshop like colourings.

Step 6: Go onto Adobe Photoshop Express and add your final colouring and then you are done.

One word of advice, don't make a bookmark in PicsArt