Congratulations! I was also approved last week, only a $2500 CL but more than enough for the $150 spend bonus and 6 months of 2% rewards, after which it won't get much use.
Now the fun part - creating an online account on hsbc.com. First rule: Don't be in a hurry. I tried to create an account as soon as I got the card, I'm the opposite of a procrastinator. 
Among other things it asks for the card # & PIN, which I thought was stupid as a CC doesn't have a PIN. So I called the phone # displayed on the screen - at least 10 minutes of security screening, including sending me a text message with code. I gave the rep the cell # I was calling on, but she said she couldn't verify it as a U.S. # (it's Verizon), so she sent a recording w/code to my landline. Finally all set, and she had to send a link to my email and a temp password text message to the cell # they couldn't use a few minutes before. 
But you know what? They did send me a PIN, came in the mail yesterday, 10 days after I got the card. So it will be much easier to wait until you get the PIN to create an online account. Once you do setup an account, I had to use Chat to figure out how to add an external account to pay the CC with - with your CC account displayed, click the text "View Details" in the upper right. That opens a new tab where you can add external accounts and make payments to the CC.
Working with HSBC is a adventure. . . .