Glow (Inner) is a function that adds light to the inside of the line. You can add a three-dimensional feel to handwriting, or text fonts by using this function.
Prepare a font you would like to add Glow (Inner) to. (shown is a handwriting)
Open ①the Layer window, and tap ②new layer to add a new layer. Select ③the current layer. Move it over the layer you would like to apply the filter to.
From ①the Tool Selection window, select ②Filter.
Select ①Glow (Inner).
Turning on ①Crystal Glow makes the outline clearer, and adds a more three-dimensional feel. Drag ②the sliders left and right to change the radius, color, and more.
Once you are done making adjustments, tap on ③✓.
Open ①the Layer window, and tap on ②eye to make it invisible.