Here are the recommended guidelines for your DM.
1) Say Hi and introduce yourself.
2) Try to add value.
3) Keep it short.
We recommend that you DO NOT:
1) Make any HARD calls to action.
2) Put a link to your website/offers (you do this when you follow up but look like a spammer when you do it on first contact)
3) Do anything else that makes it look like you are trying to TAKE before you GIVE.