We have a few program specific tips on our website about how to send email attachments. Each step is broken down step-by-step.
I am writing this more as a general guide for emailing attachments. I have seen a few mistakes lately that have caused problems for first-time attachment senders. Here are a few tips to help you avoid problems.
1. If you are emailing photos and you use Outlook, Outlook Express or gmail, download and install Picasa – selecting, resizing and sending photos is a one step process.
2. Don't ever scan a document as "text" when scanning. Sometimes this will open the scanner software's OCR feature which converts it to a text document rather than an image. This sounds good, but it will cost you a lot more time and it probably will just frustrate you.
Even if it does scan the text as an image, it will be a very poor scan, similar to what you get from a fax machine print out. Scan the document as a color or grayscale image and you will be fine.
3. Scan at 72-96dpi. Every scanner lets you make this change before you scan. You will have to look for it. If it's a digital photo from a digital camera, either use Picasa and one of the email programs mentioned above or download, install and use the Microsoft picture resizer to resize the photo down to something you can use.
4. Avoid attachments completely. This is possible if all you send are digital photos. Setup an online photo album with Picasa Web Album, Shutterfly, or flickr.
Expect this to be a topic of a digital photography user group in the very near future.