That makes the question you asked rather disingenuous.
You get to do a bit more than that, though few ever do.
Making full use of representative democracy means continuously contacting your representative, not leaving them alone until you're convinced they'll act in your interests, and not leaving your friends/family/community alone until you've got as many other people as you can badgering your representative just as much. It's very time consuming and won't work at all if there aren't enough people with the same problem but, in the case of the author of this article, the relevant problem is quite widespread.
And at least half of your advocacy will consist of writing and research and recruiting other citizens to your cause - all of which can be done just as easily outside of normal business hours.
If you get a bunch of people with the same concern to form an ”organization“, and then you spend weeks making repeated requests for your congressman to meet with your group, they'll eventually do it. You can write a op-eds and publish content on the internet to try to generate political will. You need to convince your rep that (to go with the example from the article) thousands of their constituants think that the ACA is a terrible idea and that they would enthusiastically support this other policy in its place. If there is a sensible policy that a large fraction of the country would support that hasn't been proposed in a bill yet then they might consider trying to look good by being the one to propose it.
I'm not saying it's easy or that it's guaranteed to work. I'm just saying that most people's civic engagement is about 0.001% of what it should be if they really want a voice in the government.
Picking a candidate for President (a position which isn't even in the legislature) is not the most effective way for you to drive policy.
I wonder why it is, that normal citizens with jobs and kids and mortgages, aren't able to effectively lobby the way full time paid lobbyists (with expense accounts!) are?