Building a website feature

We run a content syndication platform on the domain [login to view URL] which is one of India's only crowdsourced content syndication platform wherein freelance content writers can submit their content to our editorial team. The website is powered by wordpress and but we do not have a "save draft" feature created for the same. So, when someone who is logged in has to submit a post, there is no feature to save the draft of the post that he/she is writing. We need to create the same as is in any other content website.