I agree with rickair7777. Setting up something you can do online will give you the maximum flexibility. Especially if you're just starting out as a pilot, you'll probably be spending a fair amount of time on reserve. When you're just sitting waiting for the phone to ring, might as well pull out the laptop and make some money on the side.
Having a side gig is also great for income stability. Nearly anyone who's been in professional aviation for very long will tell you it's not a question of IF you'll get furloughed, but WHEN. If you've got an income stream already in place, you'll be a lot less stressed than a bunch of your peers. You can also devote more time to the side biz while you're looking for your next flying gig.
Look to your skills, hobbies, professional training, or any other area where you have marketable knowledge. In our digital/online age, it shouldn't be too difficult for you to find a way to monetize your idea via the web.
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