You have created your signature template with all the required information and images. Your first initial email looks correct, but in some cases, when you reply or forward to the email, the images appear very large and not the required size for the signature template. Is it so?
This happens because some email clients ignore the Width and Height values set on the image(s) in the signature template and revert the image(s) back to the Native image size.
To prevent this issue, you must ensure that the images used within your signature design are created at the required size for the signature template.
For example, if your logo appears as a 150x150 image in the signature, then a 450x450 image must be uploaded. Advisable PNG format. The size should be up to 50kb. We recommend uploading an image with a high resolution and high DPI (300 px).
Instead of re-sizing the image in the signature template, you should create the image at the required size. This can be using an Image Editing application such as Photoshop or Paint.NET.
Next, the image must be uploaded to the signature template again.
Note: It is good practice to use a simple naming convention for the images when editing them. For example, the original image could be called "logo_original.png" when you re-size the image, you would want to name this "logo_100x100.png". This allows you to identify the re-sized image quickly.