I recommend making 1 batch using a picture frame and junk mail with nothing added except water. This will give you a lot of experience and practice without wasting supplies and you can experiment along the way. If the paper does not turn out simply add water to the blender with the paper pulp and repeat the process!
For the deckle I used a picture frame and covered the back with screen wire and duck tape. It worked well enough for me to know that I wanted to build a durable deckle because I will be making a lot more paper! I made paper all evening one night and it held up fine. If you use a picture frame, I suggest one that does not have a beveled edge making it easier to remove the paper. You could use a cloth on the back (I think), but it would take a little longer for the water to drain through. I recommend a thin cotton from a very worn sheet or perhaps a nylon stocking could be stapled to the back of the frame. The frame I used was 9" X 12", but it would be fun to make a deckle from a mini collage picture frame for smaller pages.
My husband built me a frame but after using it a few times; I wished I had asked him to make it into 2 pieces like kiteman's. He made a frame that is much easier to remove the paper. I would add a way to secure the back of kiteman's frame so it would be re-movable but would also allow you to clamp the screen to the frame section, somewhat like they use for picture frames with glass. To see kiteman's deckle look at his video: https://www.instructables.com/id/How-to-make-paper-1/
Most of the pages I made were card stock paper. If there were a way to press the pulp harder between a press of some sort; you could achieve a smoother thinner paper. Ironing the paper with a smooth cotton cloth did make a significant difference or you can use a rolling pin and wax paper. The paper I made did not fold very well, although I have a couple of sheets I made tonight that will fold nicely. I soaked the paper in water overnight and blended it longer to achieve this thickness and I used a rolling pin and ironed it.
I also used less pulp in the deckle achieving better results for thinner paper.
When drying the wet pages it is important to use a flat smooth surface and smooth cloths because any rough towels will texture the paper.
I made my paper thicker for an art journal, so I got one to two sheets of paper from each batch measuring 9" X 12".
The starch will prevent ink from bleeding on the paper when used for writing.
You can make acid free paper by adding calcium carbonate and liquid starch. You can test your pulp with a PH strip to see if it is acid free, it should be 7 or slightly greater according to: http://en.wikipedia.org/wiki/Acid-free_paper
If adding dried or fresh flowers, herbs or grass remember you only need to add a tablespoon or two and a short blend will give a more attractive appearance. A longer blend will speckle the paper.
Using junk mail will give you a muted color; If you desire more control over the color the paper will be, use white paper with no ink or after the pulp is made, place the deckle in the water bath and pour the pulp into the frame and rinse the pulp by dipping it in and out of the water a couple of times. Empty the container of water in the toilet and then refill it with water. Repeat rinsing one more time and then return
the pulp to the blender if adding the colored paper, starch, flowers and oils. Rinsing the pulp should achieve a whiter and brighter appearance because the water bath removes dies from the ink making the paper lighter in color.
I also used beet juice in the blender to color the pulp. It worked Ok but it did not color the paper as dark or as bright as I wanted because most of the color washed out in the water bath. I read somewhere by adding vinegar to the pulp and letting it soak overnight helps retain the color. I have not tried this method. Perhaps using construction paper would make a difference in the color.
I added pressed dried flowers to a few pages after the final rinse while the pulp was very wet. It worked with very flat flowers and stems. Some of the thicker stems did not stick. It was better to let it air dry because ironing the wet page caused the flowers to move.
I also added a heart from tissue paper which fused to the paper very nicely. I did not dry it with an iron.
To air dry; it is important to use a very hard flat surface with a smooth absorbent fabric between the layers and flipping the page over a couple of times so they dry thoroughly. Some of my pages wanted to curl up. As I make more paper I will refine the drying process so this does not happen. I ironed the pages that curled up.
To achieve a stronger scented paper allow the oils to soak in the pulp overnight and then place the pulp into the deckle to form the paper.