First and foremost you're going to need to clear your schedule for the rest of the day, not because applying castor oil won't grow your beard but you're going to want to take time out of your day to go slap whoever told you this awful myth.
The truth is that there is only one type of product that helps grow facial hair and if you haven't heard of it (I'm sure you have) go visit my Rogaine review to see the exact protocol to follow.
I'm guessing though that you're sitting there with a bottle of it in your hand going... really?
Well I'm glad you took the time to search because there are definitely better alternatives out there. That's the reason I only recommend a certain beard oil to people is because most others are filled with crap and make astronomical claims or they are simply something like castrol oil in a bottle (which is worthless).
The one thing I can tell you is that you're going to want to keep your face and beard as healthy as possible. It's not easy to do this when you're a man, not because we all have manly jobs like being a wrench or kicking ass but because we are hard headed and don't want to fall under the category of men who Manscape. Believe me I shy away from this term as much as possible but if you want a killer beard you're going to have to do some cleansing and conditioning.
The biggest piece of advice is spring for some quality products, I've done some reviews of these bigger box stores and you would be surprised at how low quality of products they carry. I mean I would trust this stuff on my dogs rough hair. To give you an example go visit my post on the beard products at Walmart.