Airdrops are mostly easy to join as you just have to sign up under the publishing entity.

Always read the instructions given in the announcement post, which you will obviously find at the start of topic thread. Go through it thoroughly because sometimes instructions are tricky and you may loose money for silly mistakes.

There will be either sign up form (google based) or there will be their own sign up form. Just fill in the details and then you can checkout your enrolment in the Sam thread under status doc.