Digital marketing can be hard to grasp - it has a lot of moving parts and some may or may not apply to you but they must all be considered even if you may not deploy them.. I like to see digital marketing as a cyclical process - one that repeats at a pace that is representative of the changes in your specific industry. I have found the following path a very general outline for this cyclical process. But I have been doing this for 15 years and I am still learning - for example what do you think I am missing? 
My Top Five Online Marketing Tools:
1) Buffer - schedule all your social media posts and move on! SM is important but can be a time suck!
2) SocialMention - Real time social media conversations search - research trends in SM.
3) WordStream - Doing a PPC camapign? Use WordStream to help you find niche keywords.
4) Bit.ly - Deploy custom URL's when a 301 re-direct won't work - get stats and data on whos viewing and sharing your content.
5) Reachmail - a good FREE email marketing service up to 15K names or 50K emails a month - easy WSISYG editor
