I am a shameless, hopeless romantic. Nothing touches my heart more than seeing folks in love. As such, I've written a few letters here and there (okay, like three times including Tarzan, and he honestly gets the bulk of them) and I'm pretty good at it; found out in high school one of the boys I'd written one to had used my words, with a few pronoun switches, to get another girl. Karma came, but that's neither here nor there; here's my short list of things to consider when writing a love letter:
1) Find a song that makes you feel something. I don't care who you are, music will move you to tears on occasion. I'm not saying you've got to bawl to find your perfect love letter inspiration, but you've got to be inspired. The whole of the song has to be something you feel about this person, where you hope you guys go; the song, pretty much, is your template for your love letter. I'm not saying you write down the lyrics either (that's lazy!), because that's just tacky, but listen deeply and clear your mind of everything but the song and thoughts of that person.
2) Don't try to be Shakespeare; write what you know, write how you speak. A lot of people, once they meet me, find out I blog and make their way here, say that what I write sounds exactly like who I am. The letter is coming from you, make it sound like you. Simply put, which would you rather hear: a) Lover, I nary glimpse a star-drenched eve without pondering over your proximity and if they catch your eye as well, or b) I can't look at stars anymore without wondering if you're somewhere looking at them at the same time?*
*Admittedly, both float my boat. And if both sound good to you, don't be afraid to mix the two styles up, if that's who you are and what you mean. Which leads to 3.
3) Mean it. Every word, down to the "the's" and "a's" that drive the letter forward. If it's insincere, it'll come off that way. And if you wouldn't stand by it in front of a stadium full of people while having someone else read it aloud, it means it wasn't true to you, which is a big thing. In a love letter, you're not only letting this person (and any person they decide to let read it one day) know how you feel about them, but you're letting them know who you are and how you feel. If you can't stand by how you feel, proudly, why would they, after reading it, stand by you?
4) If you're not comfortable with someone other than that person reading the letter, don't write it. Instead, see #1 and make them a playlist of other people's stuff. Getting personal with someone else is a big step with no guarantee that they'll keep it to themselves, and what's more personal than writing down your possibly grammatically erred, but deeply passionate thoughts and feelings and handing it to someone? If you're not ready, work your way up until you are.
5) Make it cohesive. A page full of the words "I love you" written over and over is not only limited but entirely creepy (and lazy! Put in the effort!). Just like in high school, when teacher told you to state your point and the beginning and end of each paper, make sure whatever story the body of your letter tells you go back to the main topic (which you stated at the beginning. Something to the effect of "I think you're super dope") and the end to bring it all home.
6) Make it (or them if you're writing a few of them at a time) something special. I write something everyday, whether it's here or a diary or, yep, love letters to Tarzan. The difference with the work I put here, the work I put in my diaries, and his letters are simply dates. The reason being that my feelings and who I am don't need to be time-stamped. It may not seem like a big deal, but no matter which letter he picks up, I know (and hopefully he knows) that whenever he reads them, they're going to be true, and it's going to be who I really am. You've got to find something to do with your love letters that make them special, to make this person realize they're special. Spray perfume on them, draw stick figures at the bottom and create a flip book, put the cheat codes you use to whup them at video games at the end of every letter in very small print...Whatever you guys share, whatever is special and fun about the two of you, incorporate it.
Coming from a girl who's written a small box full of cursive, undated love letters for the person who means the world to her, this isn't a fact just an observation: it feels great. Letting them know how you feel on paper (or by Microsoft Word), releasing the feelings out into the world, frees you and them. In all honesty, what the omnipresent "they" say is true: the worst the person can say is "I don't feel the same." If you never let them know (whether in love letter form or not) you'll never know. And we all need a lot less "what if's" in our lives. And so what if they don't feel the same? You just did something brave and beautiful, and if they don't appreciate it, someone else surely will.
Be great (don't be lazy!) and share the love.