Uploading your talks ahead of time is quite straightforward, and it helps the tea and biscuits arrive on time! These instructions are replicated from those written for CM27, but they apply equally as well to CM29.
Step 1: If you don't have an Indico account, register for one here and then tell me about it so that I can associate your talk with it. Those that already have an Indico account should be able to skip this step (i.e. I should have found you on their system, but there's no 100% guarantee that I found the "right" you). If you're having trouble with the remaining steps after doing this, I'll do what I can to help.
Step 2: Log in to Indico.
Step 3: Navigate to the agenda and locate your talk.
Step 4: Select your talk.
Step 5: Select the "Add Material" option.
Step 6: Upload your talk.
Step 7: Relax and have a biscuit.