Now that you've done all your research and planning -- you've figured out WHAT you need to do, WHERE you need to do it, WHEN you're going to get it done, WHO you're going to be reaching, and WHY you're going to all this trouble -- now you need to go do the work. If you created a calendar, this is easy... you simply look at the calendar, figure out what needs to be done, then go get the tasks accomplished. Instead of worrying about what steps you need to take in order to market your book, you can begin working through the plan you've spent weeks creating. No more seat-of-the-pants, no more guessing what activities to do. You've done all the background work; now you need to put it into practice.
Authors tend to come in two types when it comes to marketing... Some will want to take several weeks and just market full-time. They'll set their current writing projects aside, and suddenly become marketers. Others will want to set aside a chunk of time each day for marketing, leaving themselves with a few hours to continue writing. There's no "right" way to plan this -- it depends on what you're comfortable doing.
I'm frequently asked how much time an author should spend on marketing each day or each week, but of course the answer lies in what your plan calls for. If you do the things that are on your plan, the amount of time required will become clear to you. Some authors set aside an hour or two each day to do some marketing. That time can increase as you have a new book come out -- so you might find yourself spending half your time on nothing but various marketing activities. If you're focused on a new release, and there are a dozen things to do each day, your marketing efforts could suck up your entire day.
Again, I realize that, as an author, you signed up for this career because you wanted to do writing, not marketing. I get it... but if you want to succeed and grow your platform, you're going to need to invest some of your time at promoting your name and your works. So just make the decision that this becomes part of your regular job. It may not be the part you love best, but every job has some aspects to it that you're not crazy about. (I get to read contracts regularly. Not my favorite part of the job... but a necessary one if I'm to be successful in my role as an agent.) Besides, you may discover that you actually LIKE doing some marketing. There are plenty of authors who, once they got into blogging or speaking or social media or writing articles, realized they enjoy the marketing aspect of their careers.
One last thought: You need to figure out what "success" is for yourself. Nobody has every element of their marketing plan go smoothly, or watch every aspect of the plan succeed in a big way. You'll have some hits and some misses. But it will help you if you've decided ahead of time what "success" is for your book. Then go work your plan. Once you've gone through this process, you'll begin to see how you can create a marketing plan for each book you write.