I realized, in order to love someone, you have to like them first.
At first, appearance (for the most part) is the first trigger to attraction between one and another. The first thing that comes to mind would probably be "He/she looks good" but then one will eventually think; "I like her smile" or "I like her eyes". Then from that point, more likings comes and it'll deepen the attraction.
But when it's already love, things will change. Looks would still matter, but you won't say "I love you" just because your significant other looks good. You'll say "I love you" because he/she made you breakfast first thing in the morning. You'll say "I love you" because he/she did some of your homework (which was piling up like crazy, making you fall asleep sooner than you thought) without you noticing so when morning comes you're good to go. You'll say "I love you" because he/she did something special, making your heartbeat skip faster than usual. You'll say "I love you" because he/she did something bad causing you to get mad and/or fight but it soon ends in kisses and cuddles.
I realized ... When you love something, everything is possible.