How do I receive and read large PDFs on my iPad?

So someone sent me a largish PDF book today and it's on my macbook pro. I want to read it on my iPad. I tried to Airdrop it, but the image of the book just sits in the Airdrop window. On the iPad, I don't see a way to open Airdrop, there's just the General, Contacts Only, and Everyone for 10 minutes lines on the General pane. I tried dragging it to my Kindle for Mac on my computer, hoping that it would somehow become available on Kindle on my iPad. Nope. Nothing there. I tried to email it, but it's too big. On the iPad I hit the cloud thing to download the attachment and it says it will be "Available in Mail Drop for 30 Days." That's interesting, but I don't have Mail Drop. So I ordered Mail Drop from the App Store, but the sign on was screwy and said I had entered the wrong password when I didn't yet have one. How can I read this thing on the iPad?