On top of the Write box whether you’re editing an existing post or you’re composing a fresh one, there are two options: 1) Visual and 2) Text.
Visual is for the normal language editor, while Text is for HTML code, clicking on Text will switch to HTML editor.
For security reasons, all codes aren’t not allowed by WordPress, the accepted HTML tags are: “address, a, abbr, acronym, area, article, aside, b, big, blockquote, br, caption, cite, class, code, col, del, details, dd, div, dl, dt, em, figure, figcaption, footer, font, h1, h2, h3, h4, h5, h6, header, hgroup, hr, i, img, ins, kbd, li, map, ol, p, pre, q, s, section, small, span, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, var.”— Inmotion Hosting
Adding HTML codes to an existing WordPress Post
You can add HTML codes to an existing post by locating the post in your All Posts and clicking on edit.
Click on Text, locate your preferred place, and paste your code: Your code could be an affiliate HTML codes or other promotional codes created by you or your business partner.
Click on Update by the right handside of your dashboard.
That’s all. Check your post to be sure your code appears in the best suitable place.
When you’re posting again, don’t forget to switch back to Visual if you’re not adding any code.
Adding Code to WordPress Sidebar
If you want to add code in your sidebar, make sure that your theme support the widget you want to add, by using a text widget under Presentation–> sidebar widgets and you have to be using a theme that allows widgets.
*Check sample HTML code of one the products I promote below this post
WordPress Plugin for Code
If you don’t want the manual means, there’s also a plugin for adding code: Insert Html Snippet
Featuresof Inser HTML Snippet
The shortcodes generated using the plugin are easily available as a dropdown in the standard wordpress content editor as well as in widget settings, thereby giving you ease of integrating your HTML snippets with your posts and pages.
If you prefer the plugin, you can download it
How to manually Add HTML Code Blogger Post or page
While there are plugins for virtually everything you want to implement on WordPress, most of such actions are manually done on Blogger, Google’s own free blogging platform.
This is how to add HTML code to an existing blogger post
Login to your blogger dashboard
Click on the post you want your code to appear
There are also two options by the top left handside of the post box: 1) Compose, 2) HTML. Click on HTML.
Paste your code, and click on Update. View your post to make sure it works fine.
You can also add code to a blogger page. All you need do is click on the page, switch to HTML editor, and paste your code