How do I activate/deactivate or delete my campaign?

You can easily control the campaign to be active or inactive. You can do it within the administration interface of your OptiMonk profile where the list of the created campaigns can be found. If the campaign is active and you wish to deactivate it, just simply click on the green "Active" button and it turnes to be red, saying "Inactive". If there is a campaign you do not need anymore and you wish to get rid of it, click on the X button on the right side next to the campaign statistics.