I started by creating some sketches to have a general idea of how the letters were designed. Then I moved to Illustrator. Fontself Maker has its own template that is very useful since it's set up in a proper way. It has the correct color mode; the guides and layers are established in it; and it has all kinds of letter shapes including Cyrillic letters which can be used as a guide to drawing your own. To use, open the Fontself panel (Windows > Extensions), open its panel menu, and select the template from it. You can follow their instructions there.
However, I decided that I would not use a template for this font because they are fairly simple and they are just geometrical shapes. Before I began, I did some research and I learned that the most important thing about a new Illustrator file is the color mode. It is best to set it to RGB when designing OpenType-SVG color fonts. If you work from a CMYK file, Fontself will convert the colors based on your color management settings.
Creating Grids and the Baseline
After configuring my document, I set up my baseline using the Rulers and guides (View > Guides > Make Guides) and I named the layer "Baseline1". This will be important later when you start importing letters in a batch. Fontself recognizes guides by their names: ascender, cap-height, x-height, baseline, and descender. I created 26 simple 4x6 grids for the regular English alphabet and set them up on my Baseline1. Then I added additional grids for the accented letters on "Baseline2" below. However, for the accented letters, we cannot use the batch importing option: we need to add them one by one as glyphs. For the grids, I created a simple rectangle with the Rectangle Tool, then clicked on Objects > Path > Split to split into a grid, and I entered the number of rows and columns.
Once the grid was ready, I started to draw the letters using the Pen Tool and the Arc Tool. When I was done with the drawing and had the shape of the letters, I selected the whole object one by one, clicked on Object > Live Paint Brush > Make. This step makes it possible to use the Live Paint Brush. The Live Paint Brush is a remarkable tool because rather than painting or filling the whole object, it recognizes shapes and lets you chose the area to be colored. And this is exactly what we need in this particular case. I had previously set up my color palette using 6 different colors. Then with the Eyedropper tool and the Live Paint Brush (K), I filled out the desired areas.