Using these tools is very simple and easy. These are free to use tools. Some sections or images may need pro access so there are in app purchases. These four are my favorite tools.
Canva - Canva is a graphic design platform that allows users to create social media graphics, presentations, posters and other visual content. It is available on web and mobile, and integrates millions of images, fonts, templates and illustrations. Canva helps you create beautiful designs, not just social media but things such as infographics, posters, brochures, flyers and many more.
Crello - Create engaging social media graphics. It is free to use graphic design software. It is the simplest online image editor. Crello lets you create your own designs, Post, Cover and Animations. Use the best online design software. It's easy and free!
Pablo - Pablo by Buffer helps you design engaging images for social media that increases your social media engagement. With Pablo, you can create beautiful images easily to make your posts pop.
Piktochart - Piktochart is a web-based infographic application which allows users without intensive experience as graphic designers to easily create infographics and visuals using themed templates.