To participate in the market, first you need to make a channel
You need to wait until the new_channel tx is included in a block before you can make any bets.
You need to download all the headers before you can make any bets in the market.
if your price is 25, and the amount you bet is 1, then at most you can win 3, and at most you can lose 1.
If your price is 75 and you bet 3, then at most you can lose 3, and at most you can win 1.
price is the same as percentage odds.
When your bet is successfully accepted, the "amount" should disappear.