You need photo bucket app and to save image if your are using a phone you have to open it in safari or Internet not through the app.
To add to signature first create photbucket account and then upload photo and the look at picture above to hold finger on i. Copy the web address and paste it in signature
After you upload a photo then Hit the i button
copy and then past the circled link into your signature when editing your profile. You have to hit save lol.
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