I'm a wedding planner. Here are 11 easily avoidable mistakes I see many couples make.

The processional — or the order in which your wedding VIPs enter the ceremony — can be a lesson in diplomacy, so I recommend the couple discusses this before the rehearsal.

You're much less likely to offend someone if you're not making a choice about them right in front of their face.

An easy way to set yourself up for success on your wedding day is to unwrap the items you've bought, such as decorations.

Ideally, you'll start on this a few weeks before the wedding, but uncoiling a million fairy lights or unsheathing 100 umbrellas can also be nice, mindless tasks to calm those night-before nerves.

The goal is to have everything ready to go for set-up the next day.

It's extremely helpful if you tell your vendor team about any kind of family dynamics that could cause hurtful or awkward situations. For example, maybe your parents aren't on the best of terms so they shouldn't be posed next to each other during photos.

That kind of intel is helpful for your team. When in doubt, prioritize these conversations with vendors like your photographer, videographer, planner or coordinator, and officiant.

Unfortunately, many vendors wait until the week of a wedding to send you time-sensitive requests like final questionnaires.

If you're not planning to regularly check your email the week you get married, it's best to say so.

An out-of-office or "away from computer" automated message does wonders, particularly if you share other ways these people can get ahold of you if they really need you.

If you're having your guests pick up their own place cards to choose their seats at the tables, lay them out alphabetized by last name. This will make it easy for your guests to quickly find their cards.

If you're assigning specific seats, organize the place cards by table. You can group the cards in individually marked envelopes (like Table One, Table Two,) and in the envelope, organize the cards in the order you want them set out (like Rashida sits next to Mike who sits next to Padma).

If you have more than 50 guests, you'll also want a sign or another way of telling them where their assigned seats are so they don't have to check every single table.

More than once, I've been handed a wad of $100 bills and told to distribute at will. Though I'm happy to do this as a couple's coordinator, it's not necessarily the most effective way to tip your team.

Instead, research how much you should tip and put the designated amount in labeled envelopes for someone else to distribute before each vendor's shift ends.

If day-of tips just aren't in the cards, follow up within two weeks after the wedding to compensate via Venmo, PayPal, or however you paid your vendors originally.

Forgetting your marriage license happens more than you think. Skip this last-minute errand and get your marriage license a few weeks prior to your wedding, if possible.

It's also good to keep an eye on when you can officially apply for a license. For many states, there's a specific window of time before and after a wedding when you can apply for and return a license.

Getting a certified copy of a marriage license ensures that the document was actually received and filed by your local government.

Certified copies are also important for verifying your identity if one or both of you are changing your last names.

Typically, your marriage license will come with a worksheet to fill out to request a certain number of certified copies (I suggest three) as well as details on how to pay for them. I recommend paying via check for the marriage license so that there's less lag between when the document is filed and when you receive proof.

This may sound silly, but knowing how much daylight you have is important for photos, particularly if you're getting married in the fall or winter when the sun sets early.

When you're timing the shoot, keep in mind that most wedding photo sessions usually take 90 minutes, divided among the time it takes to get pictures of the couple, wedding party, and family.

If you're taking photos before the day's events, end the session no later than 30 minutes before the ceremony starts.

If you're looking to get the best light for additional photos, remember to block off 15 to 20 minutes during golden hour, or the hour or so before the sun sets when the sun is softer, redder, and makes us all look like supermodels.

This always happens without fail and leads to a lot of frustrated guests.

Avoid the complaints by seating those who probably won't frequent the dance floor further away or, at least, not right next to any kind of speaker set up.

Unless you're the type of person who writes best under pressure, I recommend designating at least an hour during the month before your wedding to work on your vows.

Couples will often wait until the night before to start writing, which typically works out but eliminates the transformative, emotional experience of reflecting on why this is the person you love enough to marry.

If you're struggling to find the right words, you can also consider a vow-writing workshop. They're often cost-effective ways to get the words flowing and a fun reason for a date.