Check-in with Iberia
Anyone flying with the Spanish national airline can check in 24 hours before their departure and download their boarding pass remotely (up until an hour before the flight takes off). All you need is your booking code and you can check in online and select your seat at the same time.
Baggage
Cabin luggage cannot be larger than 56 x 45 x 25 cm. Baggage weighing between 23 kg and 32 kg attracts an "excess weight charge", while anything over 32 kg cannot be taken in the hold.