The most important thing to do right now, other than educating yourself, is to keep accurate and reliable records of your income and expenses. "Reliable" means that you have enough detail to verify the business purpose of the expense, and that you maintain the records contemporaneously with the expense -- you make the record close enough in time to incurring the expense that your memory is considered reliable. (It would generally not be considered reliable to reconstruct your expenses only when preparing your tax return.)
This includes not just receipts, but some kind of spreadsheet, accounting program, diary or account book that lists the date, amount, and purpose of the expense. If you use a personal vehicle in business, you need a log book, diary, or app to keep track of the date, mileage, and business purpose of each trip.
You may want to buy a small business tax guide. "Lasser's" is a brand name I know of, although there are other similar guide books.
