Yes, you should!
Know each character perfectly, so make sure they're in character, which is harder to do with Dramione, but that's the fun part about it.
Plan out the story before writing it, you want it to make sense as much as possible.
Make sure Draco and Hermione actually form a friendship before being romantic or just make sure they grow together as characters and get to know each other.
Use correct grammar.
Complete the story.
Make it romantic!
Please, no side character relationships. Especially, Harry/Pansy, Ginny/Blaise.
Make it about their time while in Hogwarts. No Head girl or Head boy fanfiction. Too much fanfics on that already.
Or it can be during war.
I like really fluffy, cute Dramione stories, but a lot of people like smut, so go with your instinct, but overall just have fun with it. :D
before i say anything else i suggest you reread the books first. if youve only read fanfics recently than youll end up falling into a pattern that can turn into a terrible writing style.
a few things ive noticed that fanfics tend to do is to slowly go OOC (out of character) and people eventually stop noticing. if youre looking to have yours believable and more authentic then note:
draco doesnt just smirk. for some reason fanfic writers like to use that word it is an awful word. it carries meaning and personality that generally doesnt fit draco. the only time that i can think of where it would be appropriate would be when he gets the golden trio in trouble/has a teacher on his side. its kinda when a little brother gets away scot free while youre in trouble. otherwise he would not smirk.
also people act like draco secretly has always loved hermione. c'mon. no. unless its from his POV and you logically explain why he'd be interested or put them n a situation where at a believable pace they become interested (and it would just jump from hate to love at the drop of a hat. baby steps, people. baby steps)
and i guess the last thing would be to not say he became interested through jealousy. as if! he has absolutely positively no reason to give a flying flip about hermione and jealousy would be like saying that sylvester was jealous or possessive (also an OOC word) of the roadrunner, because Wiyle E. Coyote has "suddenly" (not really) taken up an interest. Sylvester has tweety. thy dont even show up in the same skits as Wile E. so he doesnt care. roadrunner can be chased by tas for all sylvester cares.
no one can tell you what to write about. if you want to write one then you should but do an original storyline with your own ideas. it will be more interesting for everyone that way. if i were you read a couple, read the books and think about it. im working on one and i am really excited about releasing it because the plot feels fresh.
also, a good tip is if you are ever reading fics and you get bored and think "why do they write the same plot?" and start thinking about better ideas, or you think of something and wish someone would write a story on it, or you try to find a story with a certain plot but there isnt one. write "that plot" yourself. call your own bluff. that should also help to motivate you and make you feel more creative because youll know it will be appreciated.
ps. one more thing. dont just start writing then post teeny tiny tidbits because you think its good. its always painful when a writer keeps leaving you on cliffhangers. make sure you have something solid before posting so you dont end up giving up and quiting half way through.