If you are targeting an audience that is active on LinkedIn consider having a paid account so you can use the InMails. You can message limitless amount of LinkedIn members even if you are not connected to them, best of all is that is you don’t get a reply you don’t have to pay for the sent message. Make sure to have a template that is concise, honest and to the point, make sure not to directly jump to a sales-focused pitch but try to first introduce yourself, give some free consultation and scale up one step at the time. These are some great templates to get started with.