Should you write your own vows? Why not?! It's your wedding and custom vows will make the ceremony that much more unique to you.
The first step in writing vows is to gather some inspiration. Take a look at what you can find online; see if you can't find a few lines of prose to guide you. Think of this as a template. But that isn't all the inspiration you need. Sit down with a piece of paper and pen. Make a list of the best experiences you've shared with your partner, the qualities in your fiancee that you love, and a few fond memories.
Get to work writing! Here's a few things to include:
"I love you". This is a wedding after all!
A few promises. These can be serious or humorous. You can tell your beloved that you will "be there through thick and thin" or say that you will "wipe your runny nose" or anything else that is meaningful and authentic to you.
A good story. Weave in an anecdote that illustrates what you love about your fiance. This makes things concrete, and paints a picture for your guests.
Your community. You will need the support of your family and friends in your relationship. It's ok to acknowledge that.
Your spirituality. This is optional. If you have a spiritual life, feel free to say so.
Something heartfelt. This isn't a distinct point so much as an attribute of all the other elements of your vows. If you write something that's from the heart, it won't come across as saccharine.
No absolutes. Skip the absolutism. You can say that you'll "never get angry", but that isn't going to happen.
After you have written your vows there are two things you need to do. The first is practice. The second is to make a decision about whether you'll share them with you fiance before the ceremony.
Practice makes perfect, or so they say. Whether you will recite your vows from memory or repeat after your officiant, you need to know your vows inside and out. You might be flustered or feeling emotional during the ceremony. If you know your vows, they'll roll right of your tongue. Now, will you recite your vows or repeat after your officiant? I strongly recommend couples repeat their vows when they are read to them by their officiant. Why is this so? Whether you're feeling sentimental or excited, it's easy to forget a word, or to go too fast or too slow. Your officiant will set the pace and keep you from getting tongue tied. You could, of course, read your vows. That's a perfectly valid way to deliver them, however sometimes words read off the page can come across as stilted if you're not familiar with that style of delivery.
To share your vows before the ceremony or not to share, that is a fraught question. I've seen both. First let's cover the reason against sharing them with your fiance: it's incredibly romantic to surprise your soon to be spouse with your vows. Vows are a gift to your partner, and surprising them with your vows is beautiful. On the other hand, there are a few good reasons to spill the beans, so to speak. First, sharing your vows in advance means that you can make sure there's parity. If one half of the couple professes undying love in flowery language, while the other uses a few uninspired lines, it could be awkward. Now, if you want to work toward parity but you don't want to spoil the surprise, your officiant should be willing to help the two of you out by taking a look at what you've written. The next reason has to do with how you feel about the feels. Hearing your partner's vows for the first time can tug at your heartstrings, and if you adamantly don't want tears, it might be wise to share them in advance.