One self-portrait idea is to capture an "average day" that you experience. For example, take self-portraits the moment you open your eyes, in the shower, eating breakfast and driving to work to show the progression of the morning. The portraits may be taken at exact times, such as every hour, or just randomly throughout the day. Then assemble the images in chronological order and print them on a large poster. As a twist, you might try placing the images in reverse.
Capture yourself in a a reflective surface such as a mirror, window or glass table. Determine whether to prominently feature yourself in the surface or maybe just show a small portion of your face. Collect a number of interesting shots where you're captured in reflective surfaces and use an online publisher to self-publish a book. Friends and family will have fun identifying you in each photo.
Instead of just focusing on your face, create a self-portrait project where you focus on other body parts. Ideas include shooting nude, such as pieces your bare arm or leg, or clothed, where you wear different outfits over those same body parts. Create a poster where the pieces of your body are placed next to each other for a large portrait of you. As a twist, take these portraits when you're in the middle of an activity. For example, you might take a picture of your arm while performing a weight-lifting curl. Or you might take a picture of your hand when squeezing an object. Whatever your choices, create an interesting mosaic using the parts of your body.
Everyone experiences an array of emotions during their life. Happy, sad, angry, hurt, vengeful and melancholic are just a few examples of different emotional states. Create a self-portrait project where you capture yourself in each of those states. Aside from what your face looks like in the photos, change the surroundings and lighting of the photo to reflect the mood. For example, when you're happy, you might shoot in bright sunlight while lying in an endless field of green grass. To capture a hurt state of being, you might shoot yourself in a darkened room with very low light and draw a symbolic scar on your face with makeup. Assemble these photos on a poster or in a book.