Even with websites like Wix, Squarespace or WordPress that have tools that allow you to build your own website, it's still not easy to build a website that looks professional. With so many things to consider such as how to organize navigation, what images tell the best story, how to effectively use white space, making sure spacing is proportional and consistent and testing the website layout on multiple devices, it's easy to make mistakes.
Below is a before and after example of a website that I recently re-imagined. Technically, both websites are exactly the same because they have links to the business email, provide the business phone number and describe the services the business offers. But it's immediately obvious which one was created by a professional website designer with 20+ years of experience...
Besides the 20+ years of experience, I use an arsenal of tools such as Illustrator, Photoshop, Atom, Meteor, iTerm2, Premiere, Chrome DevTools, Google Analytics, Google Search Console, Google My Business and Dreamweaver along with modern technologies and frameworks like Sass, Bourbon, Git, GitHub, React, BEM, CSS3 and HTML5.
The most important tool that I use is attention to detail. And that's a tool that can't be purchased. You either have it or you don't.