If you haven't already seen a doctor (I'm assuming from your comment above that you already have and that's where the timeline comes from), I'd strongly suggest doing so. Take their advice very seriously: If they say don't compete, then I'd strongly advise against competing.
Beyond that: Let the body do its thing and heal. This means the standard advice applies: Stay off of it, get the proper nutrition and eat at least maintenance-level calories. Don't do anything to exacerbate your injury or the surrounding areas.
A lot of things you wouldn't expect can exacerbate a toe or an ankle injury (I couldn't do pushups with my last sprained ankle). This includes things that do not hurt: walk on it less, even when walking gets to the point where it isn't painful. Listen to your body, and then take a few good steps back from that.
Conditioning wise, I'd limit what you are doing significantly in terms of physical training. If your toe is so bad that you are having issues standing flat footed, the vast majority of technique training is right out. What you can still do is mentally prepare:
- Watch videos of people competing in your art or in related arts. Analyze them. Or just watch things that inspire you. It sucks not being able to move, but you can sometimes come back much stronger with a little rest and mental preparation.
- Keep attending practice if you can physically make it and watch the class. Teach if you are in a position to do so, but at least watch.
- Meditate. Practice breathing meditation, just focusing on your breath and staying present. I've recommended Breath by Breath as a book guide, but there are a wide variety of possibilities out there.
Then, in four weeks or so when you are cleared to return to practice, take things slowly. It will be tempting to rush in, which has a high chance of being disastrous for you. Take it slow.
Then if all is going well, talk to your doctor and see if you are farther along than anticipated, but be ready to bad news. If you do get bad news, then you will have still spent the last five or so weeks productively and shown good dedication, even in the face of an injury.