Wedding etiquette expert Lizzie Post, of the Emily Post Institute.

Wedding etiquette expert Lizzie Post, of the Emily Post Institute. (Handout, Baltimore Sun / March 13, 2014)

Wedding etiquette doesn't just involve knowing which fork to use when eating your starter salad -- it's way more than that.

It could involve thank-you notes, destination weddings and deciding who pays that hefty reception bill. We asked Lizzie Post of the Emily Post Institute (emilypost.com) and co-author, with her sister Anna, of "Emily Post Wedding Etiquette, 6th Edition," about how to approach those awkward situations that may arise when planning your wedding.

If it's a destination wedding, is the couple responsible to pay for at least part of the expenses of guests? On a related note, if you're a guest, is it expected that the couple pays for some aspect of the trip (flight, meals, etc.?)

The couple does not have to pay for any of the guests' travel, hotel and meals, besides the ones they are inviting the guests to attend. The only thing that we recommend is that at a destination wedding, the bride and groom usually pay for the bridal party accommodations.

What's the best way to say that, in lieu of gifts, that we're asking for cash? Or is that ever appropriate?

It's totally appropriate; it's just how you go about doing it. You never, ever, ever indicate anything about gifts on the invitation or on a separate card sent with the invitation. What you want to do is set up a wedding website, so it's a place where you can say a gift of cash is welcome but you also have gifts on your registry so people have the option of giving a gift. Some people really don't believe in giving cash and you need to respect that. Another way to do it, if you don't have a wedding website, is to have people, like your parents and the bridal party, tell people through word of mouth and say that you would like cash.

It's always a delicate balance making sure family members are invited while also taking into account a maximum number of guests. What's the best way to whittle down a family member invitee list and the best way to let some know that they aren't invited?

You don't call them up saying, "You're not invited." That's not appropriate. The best way to whittle it down is to make clear-cut dividing lines across the board. You may say no children younger than 14 years old, or only aunts and uncles, not first cousins. My cousin did that for his wedding. They didn't say anything to us but I didn't get an invitation and my parents did. Make the decision and stick to it. Don't say no children and then have five children show up. Pick something that makes sense to you and stick with it across the board.

On a related note, couples are deciding in advance whether or not to invite children to their wedding. What do you do if someone RSVPs and ignores an adults-only request?

Just like with the gifts, you never would write "no children" or "adults only" on the invitation. The invitation indicates who's invited. When that person RSVPs and writes in their children's names and their children's dinner choices, whoever is handling the RSVPs should call the guests and say, "I think there's been a misunderstanding." You could also offer to find a babysitter. We understand a lot of people need to travel with their kids — include the option of having babysitters at the hotel. Maybe it's at the reception or nearby the reception, or maybe it's at an area further away. You can also provide recommendations for the babysitters. There are different ways you can go about it. I always think it's best, if you say no children, to then try and accommodate those guests that have children. It's a way that will allow them to be able to come rather than making them choose between kids and wedding. Also be prepared that they might say that they're not coming. That's their choice.

If you know a family member or close friend may be uncomfortable with your wedding for various reasons (age, length of relationship, sexuality), do you still invite them to the ceremony?

I think it's nice to invite them. I think that extending the invite gives them the opportunity to cross that barrier. It lets them know that even if they are feeling uncomfortable, they are still welcome to attend. Another way is to extend an invitation through a family member. Have them say, "She wanted to make sure you are included and invited." It's one of those ways where people can break down that negative barrier that's up that makes them uncomfortable. It says, "You really do matter to me and I would like you there." If you think it's going to be problematic, that's a different issue, and I would discuss with close family members.

Is it still expected that you ask sets of parents to help pay for the wedding (or certain parts of the wedding)? Are there still rules that exist on who pays for what? And how do those rules apply for same-sex couples?

Everything is the same for same-sex couples. The only difference is that typically you allow the bride's parents first crack at the engagement party. Nowadays anyone can throw any of these, host any of these or pay for any of these. There is no rule that dictates this and there is nothing that then changes for same-sex couple. The traditions were that the bride's family paid for the wedding and reception and the groom's family paid for the rehearsal dinner. Nowadays anyone can pay, your grandmother can pay, or you and your parents can pay for everything together. It's totally up to you.

The thank-you note: When should they be sent out and how personal are they expected to be?

Thank-you notes for gifts should be sent out as promptly as possible. I say get started on it as soon as you get gifts. I would try to do it as the gifts come in, rather than at the end. The letter can be really simple: One line of a greeting, a line of thank you, maybe you can write a sentence about how you're going to use it or how excited you are to get it, then a closing. Split the list up between your soon-to-be spouse.