If you are working on a pulse but have not scheduled it yet, then you simply need to hit "Remove" from the pulse editing view in order to delete it.
For pulses that have been on the schedule before and become locked, it is not possible to delete them from your end anymore because deleting it, would also delete the historical results associated with it. If those results were an internal test of the tool, or simply not relevant anymore, then we can help you remove them through our support team, just send us an email to help@andfrankly.com.
We can also help you remove the results while keeping the pulse, but we cannot remove the pulse and keep the results.