I find this article How to make your voice heard in Washington by George Miller and John Lawrence published in the LA Times on February 15, 2017 to a fantastic piece containing detailed strategy at how to get a face-to-face meeting with one’s representative. They further discuss best practices for how to conduct such meetings as well as suggesting when are the best times to pursue them. I think you will find the article very informative.
Check the “full calendar” listings on Web pages for the House and Senate — or use the portal at the Library of Congress website www.congress.gov — to see when a district or state “work period” is scheduled (one begins this weekend). That means your representatives will be in their home districts.
If you have trouble accessing the article on the website below is a PDF version of the article.