First of all Where are you from?(just curious to know) Even if you have a good professor you have to study lot for organic. The reason i asked where are you from is because in south asian countries like India they teach most of the organic in high school so it's not that bad for people like me who gets 90's on the tests. Also what textbook are u using? I have L.G.Wade and looks very easy to understand and covers everything you need to know. The key to success in organic is get the basics straight in your head i mean the geometry cis, trans, nomenclature etc. Try to make friends with students who are comfortable with organic. Also seek help from a tutor if necessary.
Beleive me, make it interesting, study hard and i practise the types of questions that your teacher will ask on the exam(i mean if he hands out practise tests before the exam). I am not an expert but it works for all of my classes.
The most important thing is this DOn't think/listen to those people who say that organic is a hard subject. It matters because it changes the whole attitude towards the subject and the way you look at things