First make sure you have an Icon wallet with a few ICX in it.
Use the tool to reduce the size to around 100 kb.
Then, simply right click and copy the image address. Load your wallet and paste that data in the data field and send a transaction to yourself, or who you wish to share an image with. It can never be changed or hacked or lost due to a server failure or malicious intent. It is decentralized and will be forever yours. Made with love by Icon-4-Business