It's my first time when I booked a multi-stage flight, essentially in the same reservation I bought a ticket from Bucharest (OTP) to Santorini (JTR) via Athens (ATH), so OTP-ATH-JTR. So two flights under the same booking reference number (PNR) as Aegean Airlines call it.
Only cabin luggage, no checked-in bags.
The JTR flight leaves after 4.5 hrs after I land in ATH, so plenty of time to go around (I don't know how big ATH is, but it shouldn't matter), but I'm unsure what steps should I take to board my connecting flight in ATH to JTR.
The check-in process, is it the same? 48 hrs before the flights. Will I have to do the check-in for each flight? After I arrive in Athens, my ID will be checked, then what? Usually, this is the step where I look for the exit signs in order to find my transfer to the hotel (or the place to get my checked-in bags, but this time there are none).
Any gotchas I should be aware of?
Optional: I'm not sure if we remain in "international space" or in Athens we enter Greece to board a domestic flight... not sure if it matters anyway, but nice to know.