Logic Pro sharing to iTunes

Hi, I've been experimenting with Logic Pro and I'm trying to share my works to iTunes with hope of sharing them to SoundCloud or Spotify in the future. But an issue I'm facing is that when I share the song, it plays quieter in iTunes than it does in Logic. I had this issue with my older Mac when I was using GarageBand, too. I've looked around some and seen people recommending adjusting the normalizing or soundcheck, but I don't know if I'm doing it right. Any tips would be appreciated!