Hello J.,
have someone take the baby for a few hours. make a simple meal and dress up the table. and if you're the card playing type... play some poker ... like s t r i p poker. (I don't know why I came up w/ that idea, since I've never even played poker before but sounded like a fun game for an anniversary night) I've seen poker chips at the dollar tree store. for less than $5 you can decorate the table, get cards and chips.
or plan a scavenger hunt around the house. plant some clues about when you met, where you went for dates, etc.
find online couples questionnaires and pick a few questions that would be fun for the two of you to talk about.
for example here is a questionnaire from a wedding planner:
1. Why are you having a Celebrant wedding?
2. How did you first meet? How did you feel about the other one at that time?
3. Where was your first date? What were the first words you spoke to each other?
4. When did you first fall in love? (How did you know?)
5. When did you decide that you wanted to be together forever? Why?
6. How did you propose or accept the proposal?
7. What do you love about your partner? What qualities do you most admire in her or him?
8. What does your partner do that always makes you laugh?
9. What actions of your partner’s says “I love you” to you?
10. When do you or did you feel closest to your partner?
11. Would you like to share any touching, funny or revealing stories about the two of you?
12. What are your hopes for the future?
most of all have fun. don't get too tired planning. ~C.~