First day, answer all the little questions first, not all are relevant in all circumstances but you get the idea.

1. Where's the bathroom?

2. Where's the fridge, etc. What are the typical patterns for people. Do they bring lunch, go out as a team etc.

3. If they are new to the area, tell them where to find all the normal things. Food, Grocery, Drug Store, etc.

4. Tell them when they will get their first paycheck, if the amount will be a partial amount tell them that. This gets looked over way too often. Tell them the pay cycle, and any benefits information have it ready and laid out. Being a startup you likely have little to no benefits, so remind them of that as many times stress of changing or getting a new job has people flustered.

5. Make sure you are ready for them, have all the documentation, legal requirements and stuff out of the way.

6. Make sure you tell them what to bring their first day so they don't feel unprepared and so you don't look disorganized.

7. For engineers, give them their machine and have them set it up. Make sure you have all the necessary access codes and have granted their accounts to everything they need before they get there.

8. Have 3-4 small tasks they can get started on, but tell them your expectations with them. If you have a lot of potential places they could contribute have a few ideas in mind and talk to them where they might want to fit in. That is awesome for most people.

9. Tell them up front, you are still figuring things out, so they shouldn't be afraid to ask questions. Make sure they feel comfortable asking questions. People who have been in startups are far more likely to already be asking questions, but just be prepared and don't get defensive etc.

10. Have fun, take them to lunch day 1 or 2. Make it their choice, sometimes day 1 is a little overwhelming and they may want to wait on lunch for a day or two so they can get the feel for things. It sometimes helps them to get away for 30-60 minutes the first day or two so they can gather thoughts, not everyone, but some people are like this.

11. Warn them of any land mines. I had a team lead one time tell me day one, look we all work really well together etc, but here are 3 things that a lot of people around here hold sacred. His point wasn't to say not to challenge them, but just to get the lay of the land first before I stepped in something unknowingly. This isn't typically an issue in startups as much.

12. Tell them where to park their car if they are driving. Or where they can put their bike if they rode in. etc. More important in larger cities, but really important.

13. Give phone numbers and email addresses in a list for anyone they are likely to need to contact. Don't rely on them searching it out in Outlook or some directory someplace. Print it out and hand it to them, or already have emailed it to their new email address.

14. Your a startup, have some sort of swag to hand out. T-shirt, mug, stickers etc. This isn't an absolute requirement but it makes people feel welcome. Yes, some people will say that's stupid, but usually these are the same people that will later say geez, they didn't even have X when I started.

I could probably go on, but this is long enough. Sadly I have learned most of these from being on both sides of the table. And you won't believe how much less stress you feel as a founder when you knock most of this stuff off the list and have it ready for them day one.

BTW -- Congrats on getting your first hire!