The trait uploader has a couple of options that you will need to choose from depending on the progress you've already made on your collection.
Choose this option if you have already generated your collection, either with another generator or a CLI tool. Your token and metadata files will need to be numbered from one (i.e 1.png) to the desired supply of your collection.
Choose this option if you have all of your trait files ready but have not yet generated your collection. Here you will be able to design and generate your collection.
Click continue to start uploading your traits and move on to the next step.