Depends on what you're selling... I'm going to assume that you're selling a service just to make it easier.. First thing I would do is make a video ad campaign and run it for 7 days with a decent Budget.. In the video include some kind of value that involves your service.. Like 3 tips, 5 steps, etc.. Keep the video on the shorter side so people watch the majority of it.. After that, retarget to people that watched most of the video and send them to a sales page/landing page/ top of your funnel/ whatever it is you're using.. BUT THIS IS ONLY IF YOU HAVE NO ASSETS IN PLACE ALREADY... If you have a following/ an email list/ an audience/past customers then I'd do something totally different.