It’s fairly straightforward to open an account. I believe the bank will ask to take a copy of your cedula (your government issued ID card), they’ll want your phone number, e-mail, and address. They may also ask for a utility bill to verify your residence.
But, you can actually have an account set up before you get your residency visa. It’s best to consult with an attorney on how to do this, but I believe that if an attorney verifies that you’re in the process of applying for your visa the bank will go ahead an open an account.