Recently I have changed my Blogger logo to ‘DD’ (Da Decoder) using Favicon. Blogger or Domain both needs a square image to add logo.
Here are the simple steps to make an Image or photo Square.
Right click on the image and select 'Open With' and choose ‘Microsoft Office Picture Manager’
Picture manager opens with your image then go to Picture>> Crop
1. On the task panel you can see Original Dimensions and New Dimensions.
2. Adjust crop handlers carefully till ‘Left-Right’ & ‘Top-Bottom’ Dimensions become equal.
3. Make sure you do the cropping to the center of the image (or) your desired position of the image.
If your New Dimensions of the image are equal then your image is squarer. Click OK and save your square image.
Now you can use this square picture for your website or blog as Logo.