How to find the unicode for my custom character?
Open the characters.png image and find what spot your character is in the grid of the picture then get the Horizontal and Vertical line the character is in. Put those 2 numbers on the according spots of this unicode character \ue1HV (H for Horizontal number, V for Vertical number)

How do I display my custom character in minecraft?
If you are able to use tellraw/titleraw make a rawtext component and add your unicode character you got from above if this is done correctly you should get a character in the chat

The 16x16 per character limit is too small can I increase it?
Yes you can acutally, by making the font image bigger (Original size: 256x256) I suggest doubling the size of the picture so its easier to know what drawing are you have

I want to have my character pasted in chat how do I do that?
Using this website https://www.branah.com/unicode-converter in the second box (the one with the name UTF-16) put your unicode character code aka this \ue1HV it should on the first box convert it to a normal character by copying that you can now paste it in chat or in commands

Notes:
Feel free to use the grid.png as a layer over the font image to help you 

Written by Paty
Thanks to Brandon on Discord for the website