I’ve recently started something that has helped me in arranging songs. I’ll take the hymn or Children’s Songbook song I want to arrange and print it out in the key or keys I want it to be in. Since lds.org does the key changes for you, it makes it so much easier!
So, here’s what I do. I print it out and put it on the keyboard in front of me before I pull out my composing music paper. I play it through a few times adlibbing an arrangement. If I come up with a different melody for a phrase or chord to accompany the melody that sounds interesting, I write it on the sheet music I printed out. This gives me a few ideas for when I start to write it out.
Sometimes you’ll think of good ideas before you are writing out your music so this makes sure you get some of them down before you forget it. I have done this and it is a sad thing! It can be messy and crowded to do it this way but it has helped me 🙂