Simply enter your username/email and a CloudStor app password, select which folder you like to upload and where in CloudStor you would like it to go and click Push.
There are tuning parameters and suggestions under How do I tune CloudStor Rocket?
If you have a large folder structure (including shares) Rocket may take too long to populate the To: selector. You can type a file path directly into the To: box instead. If it is a shared folder or group drive, type /Shared/ first. e.g. "/Shared/My Lab/Results" (without quotes).