1. Your business logo (approximately 600x600px)
The best file formats are jpg or png. If you have photoshop you can add white space around your logo to make it appear smaller in your signature.
Mail-Signatures.com is an online email template generator. It's a great place to start for creating your email signature.
3. IMGBB
imgbb.com is an online image hosting site. You can upload your logo there and host it there so your image is not an attachment in your email.
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