They have a tablet at the counter and it's very quick and easy. If you have visited before, it will auto-fill for you and you just have to accept. They have it set up for maximum efficiency!
You could do it online or usually the other parent can sign for them too. At least this is what we've done in the past. If they have a party booked there you should be able to do it easily on the website.
You can sign it when you get there. You check in on their touchscreen.
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