There was money to be made with airdrops last year during the Bull Run but at the moment it is not so easy anymore. A lot of airdrops you sign up for will never actually send you anything they are just there to collect personal information. You'll sign up for something and give up your details. The 'airdrop' now knows that you are into crypto and they can single you out by sending you personalized phishing emails or by launching a more sophisticated social engineering attack.

So if you sign up for any airdrop NEVER use your private email or usual password. Better use a plugin like Burner Emails (google it I'm a newb and can't post links).

This is a good read: https://  icorating.  com/report/ico-market-research-q2-2018/

(I'm a newbie I can't post links)

Q4 last year and Q1 this year were really good with regards to ICO returns. If you sold at the right time anything would have netted you a x2 or x20 return.

Success stories linger so people are still buying in. Average return for ICOs in Q2 this year was -55%. Q3 might even be worse.

So before you throw your life savings at an ICO: start small and familiarize yourself with the crypto space. Yesterday's ICOs were money making machines. Today's are not. You're late to the party. There will be plenty of opportunity to do well in this market so try to get an overview of everything and don't fall for empty promises.

Ideally just fill in an email address (preferably not your everyday email) I suppose. Bitcointalk has been hacked before (2015) and despite the efforts of the people running the forum this might happen again. This happens a lot with dozens of profiles you made for online services over the years but the difference here is that once the attacker knows you are involved with cryptocurrencies they might give your information some extra attention.

Most wallets nowadays support RBF (Replace By Fee) transactions. Without going into detail an RBF transaction allows you to re broadcast the transaction with a higher fee. It will replace your original transaction. I can't post links here so google for how this works with the wallet you are using.