Publishing WordPress themes on ThemeForest is hard. I mean really hard—but that's a good thing, because buyers need to buy the best designed and coded themes, and ThemeForest has to set the bar high to make sure they have the best themes in the marketplace.

While not letting every theme be sold sounds like a bad idea, it's actually a win-win-win strategy:

• The seller is encouraged to make and sell better themes.
• The buyers get to buy quality themes with some "standards" that they follow.
• ThemeForest gets to have a positive image and be on top of its competitors by selling WordPress themes that pass certain quality standards.

Of course, the same goes for almost all types of products people sell on Envato marketplaces; but I think it's safe to say that WordPress themes get the most attention from ThemeForest reviewers... and again, that's a good thing for everyone.

The bar could be set high for WordPress themes, but this doesn't necessarily mean that it's hard or impossible to have your theme approved. If you follow some simple steps like coding with standards and respecting the licenses of your assets, you'll be able to sell your WordPress themes.

That's why in this tutorial, we're going to go through a checklist to create a WordPress theme that can be published and sold on ThemeForest.

Important Notice: While Tuts+ and ThemeForest are both part of the Envato family, I'm not an Envato employee and this article doesn't reflect an official opinion of the guys at ThemeForest. I'm just an instructor and these are my ideas—although getting them published means that they're probably good ideas!

1. Evaluate the Quality of Your Code

The quality of your code is essential to the guys at ThemeForest: Poor coding skills can result in a soft or hard rejection. (We will look into what a "soft rejection" and a "hard rejection" means.) You must keep your code clean, optimized, and respecting quality standards.

Coding clean and optimization might make sense to you, but you might be wondering what "quality standards" you are required to comply with while developing a theme's infrastructure. Simply put, there are five standards to pay attention to: HTML standards, CSS standards, JavaScript standards, PHP standards, and WordPress theme development standards.

To get more information about these quality standards, you can check out this article from my series "Making the Perfect WordPress Theme". Adopting and complying with these standards while making your theme will be a huge plus for you, and the guys at ThemeForest won't have a hard time figuring out your theme's code.

2. Validate Your Markup and Test Your Theme Vigorously

Validating your theme is another important part of your theme's approval process, and is part of the quality standards that you've just read above—but writing standardized markup doesn't necessarily mean that all the pages in your theme will pass the HTML and CSS validation tests over W3C's tools. You must test your theme in detail with many, many types of post content and some popular plugins that can output content and invalidate your theme's markup.

To try out various post data, you can head over to WPTest.io which is described as "a fantastically exhaustive set of test data to measure the integrity of your plugins and themes". It really is an exhaustive set of test data and might seem "too much" for you; but passing this hard test will pretty much guarantee that your theme will still be valid in any case. In addition to WPTest, I recommend a great WordPress plugin named Monster Widget which, as its name suggests, loads all 13 default widgets as one "super-widget" to let you save time testing your theme's sidebars.

As for testing with WordPress plugins, be sure to test popular plugins that output or change data in the front-end of WordPress. Shortcode plugins, video embed helpers, social sharing widgets, any kind of sidebar widgets, and plugins that change or add to post content should be tested to offer a better experience for your theme's users. Keep in mind that this is not a requirement from the guys at ThemeForest, but it will be a step to get less bug reports and prevent any frustration with your theme.

Oh, and one last thing: Don't forget to check your theme with the Theme Check plugin!

3. Separate Any Kind of Functionality From Your Theme

Ever heard the term "plugin territory"? It basically is the definition of the type of functionality that can (and should) be offered by a WordPress plugin. Leaving plugin functionality to plugins is one of the most important (yet overlooked) parts of the WordPress theme development process.

Imagine that you're running your corporate website with a WordPress theme, but in time, you fall out of love with the theme. You decide to change to another theme and spend hours finding a new one. You find a really good looking design that's definitely going to fit to your website. You install it and, BAM, all your "testimonials" are gone, your "portfolio" pages are nowhere to be found, and the shortcodes you used inside your posts are missing. How would you feel?

This is the exact frustration the users of "bad themes" feel—the users are practically forced to use that theme for ever and ever. The term "plugin territory" was coined to describe the functionality that should be covered by plugins, and to prevent this kind of bad experience. You probably get it now: You have to take your functionality out of your theme and serve it as a separate plugin to be installed.

Luckily, there's an easy solution for both you and your theme's users: The TGM Plugin Activation Library. It's been created to be a part of themes that "recommend" or "require" users to install additional plugins. Using this library, you can make users install plugins from WordPress.org, a website, or even a ZIP file that's inside your theme's folders. Head over to the article where I explained how to use TGM Plugin Activation to get more information about it.

4. Make Sure Your Design Is Good and "Unique"

There are a lot of WordPress themes in ThemeForest, and it has started to feel as if there are more than a few "instances" of popular theme types. One example is "corporate themes": There are literally tens to hundreds of corporate WordPress themes in ThemeForest, and things have started to look alike. ThemeForest wants to offer different design choices to the customers, instead of designs similar to each other, so "uniqueness" is a factor in your theme's approval process.

Of course, that doesn't mean you can't use a slider or a "Testimonials" section, but you need to combine these design elements in an original and eye-pleasing way in your pages.

End of Part One

I really hope you liked the article—it's kind of an "elephant in the room" since people doesn't want to talk about too much, but it's an important topic nonetheless. Stay tuned for the second part to get the remaining four checklist items!

What's your take on this subject? Tell us what you think by commenting below. And don't forget to share the article with your friends—especially ThemeForesters!