I want to change my headers!

I have basic knowledge of WordPress, but come up woefully short when it comes to coding. I would like to change the banners on my two wordpress sites:
https://www.thisweekinforex.com/website
https://www.thisweekinforex.com/blog

I intend to simply change the existing banners to another which will be the same for each page.
However, as these sites were built for me by someone who is no longer around I am stuck!
I think changing header/banner requires using the header.php editor.
I have the new header/banner image file ready to install. Just need to know how to size and include in the coding.
Can someone come to my rescue with some advice as my Blog launch date is tomorrow!
Thanks and if more information is required, please let me know.
Aidan Doyle

Aidan:

The image in your header is actually made up of two images. I’m not sure why. But I think you can use just one image as a replacement.

Here’s the quickest way to change the header for the blog:

Change your file name to Header.jpg for the new blog header image. Your image should be 1000px * 225px. Upload it to: https://thisweekinforex.com/blog/wp-content/themes/financialbinarywp/images/

You can upload it via FTP or your hosting account using the file manager.

Do the same for the other site and upload it to: https://thisweekinforex.com/website/wp-content/themes/financialbinarywp/images/

It’s not necessary, but I would advise you to edit the CSS file. Find the CSS rule below and delete it:

div.art-Header-png {
background-image: url(“images/Header.png”);
background-position: left top;
background-repeat: no-repeat;
height: 225px;
left: 0;
position: absolute;
top: 0;
width: 1000px;
z-index: -2;
}

This is the second image and won’t be necessary any more. Deleting the code will eliminate the browser making a request for an unnecessary image.