1. Make your ecourse short like 5 - 7 days. The longer the ecourse easy for your subscriber to forget the matter of your previous emails.

2. Use double opt-in follow up autoresponders to stop accusitions of spam.

http://www.scripts4webmasters.com/arpproadv/index.shtml

3. Write one ecourse to promote only ONE product. If you keep ten product links in your ten day email course, it will look like a compiled sales letters.

4. If you are using affiliate links in your ecourse use some method to hide your affiliate links.

http://www.webmasters-central.com/t/siteprotection/affiliatelinks.shtml

5. Try to keep brief synopsis of previous emails. For example, in fourth day email keep few lines about what he received for the past three days.

6. If you have a trial product or free demo, offer it for the download. You can keep the download link on top of every email.

7. Put a link to your ecourse in your signature files on forums, articles and emails etc. It is a great way of increasing subscribers.

8. If you have affiliates you can ask them to offer it to their visitors and customers with their affiliate id. So your affiliates get commission.

9. Provide 'Unsubscribe' link at the end of all emails to make easy for your subscriber to unsubscribe if they want.

10. Track your promotional links in the emails, so to follow the results of your ecourse. (like how many people clicked on the link, who bought etc)