Splash and spill the liquid on the page, creating different shapes. Use brushes to paint with it, as if you were watercoloring. Make coffee pigment of different shades (concentrated = dark, watered down = lighter). Use fine liners once the coffee dries to outline abstract shapes. To avoid wrinkling the page, make this piece on a separate watercolor paper and glue it in your journal later.

it could be a connecting photo, sketch, drawing, painting, collage, etc.. Play with different shapes, too: you could use 3 squares, or rectangles, or triangles or hexagons, etc..

Tell about a fictional story or a true event in comic form. Give it a title. Get creative with the frames: make them triangular, round, hexagonal, …

Draw yourself a box in the middle of your page. Now, draw, collage, sketch, paint, ... whatever you like - but do it, literally, outside the box.

Photograph, sketch or paint artworks you enjoy. Write a few lines to each of them. Display them all over your page, in chronological order, ranked by preference, by color, or randomly. Title the works. Perhaps, research their respective artists also.

Draw a long, thin square on your page, vertically or horizontally. Work only within that space! Fill the square with doodles, a sketch, a drawing, a collage, a photograph, or anything else you may think of.

Collect and use elements only of one color of your choice.