Simon Sinek is the original go-to authority on finding your purpose. A great place to start is his very famous TED talkor dive straight into his books, all of which are worth a read.

For helpful guides on buyer personas and marketing planning take a look at Hootsuite and HubSpot. The HubSpot newsletter is one of the only ones I actually read every time.

I use Canva for quick design projects like infographics and social media posts, and Unsplash for amazing free to use photography. FontSquirrel is great if you need free to use typefaces.