Do you really need to showcase yourself as a good photographer? If so, you should work with more sense rather than adhering to random strategies. Just because you publish your portfolio into large scale websites, you cannot expect people to contact you. Instead, you should create multiple portfolios and address different crowds accordingly.
You can consider building a website by yourself and showcase categorized photographs. In addition to that, you should consider maintaining different blog sites with different themes and presenting them into different clienteles.
You can use your Facebook account as a good publishing tool. You can make your official Facebook homepage a very professional looking one. You can link your website and blogs to this Facebook page and start contacting your clients accordingly.
Apart from that, you should keep a good set of hardcopies of your masterpieces to present to your clients. These hardcopies may occupy some space but they do wonders when it comes to convincing clients.