When applying for jobs & internships, you need to follow-up, say thank you and move fast. People will remember you if you do, and won’t if you don’t.
Follow-up after: completing an application, interview, informational interview, or just having a helpful chat. When doing these things, remember to get the person’s contact information. Immediately after, calendar a reminder to follow-up soon. Your follow-up email should be brief and should state something specific (so it doesn’t look like a lazy template form – “I loved your advice about __”). Always, always say thanks.
You often will not be able to contact anyone after submitting an online application. No email address is given. Don’t waste a lot of time trying to find someone to contact. It’s just not worth it. The lesson here is limit the number of online applications you submit where you do not know someone at the company. Spend at least 80% of your time networking so that your applications will have a sponsor (and someone with whom you can and must follow up).
A different scenario calling for speed is when you learn of an opportunity. For example, when someone tells you that they’d be happy to do an informational interview with you, MOVE, make it happen! Don’t agonize over the perfect words or put it on the back burner. Good quality fast is better than perfect quality later. Speed shows interest, organization and maturity.