So how effective your author platform will be, depends on how well your targeting your audience and what tools and strategies you incorporate as part of your book marketing plan. (bookcovercafe.com)
A truly effective author platform is comprised of many interwoven parts: public appearances, social media profiles, links to sites where people can buy your book, links to literary journals where people can read your stories or poems, etc.. (webdesignrelief.com)
.7 Steps to Developing an Effective Author Platform (howtoblogabook.com)