How to methodically pick out coffee nuances I have been roasting coffee for years now at home. I definitely can pick out overall coffee differences (body, acidity, astringency, fruited, etc.) but when I read ratings and notes from my provider (Sweet Marias), I see very specific and distinct note descriptions of flavor that I don't necessarily get. Also coffees being 'sweet' is very subjective to me (I like pourover black but espresso sweetened). By themselves, I do not find most coffees particularly sweet in the way of fruit or sugar or caramel (from lightest to darkest roasts).

Is there a way I should be preparing my roasted coffees to notice nuances and pick out sweetness?
A well sourced coffee that has been properly roasted and brewed can be amazingly sweet. It's not the same kind of sweetness of cane sugar, but maybe milk is a better example. Milk is not entirely sweet when cold, but as soon as you heat it to around 130F, it's turns deliciously sweet. 
In any event, you will want a lighter roasted coffee. I think it can be a strange transition for people's pallets, especially for people that have been drinking a darker roasted coffee their whole lives, it becomes hard to identify a light coffee with the "coffee taste." A lighter roasted coffee preserves the sugars within the coffee, and brings out the wonderful acids and flavors that come from the fact that coffee is indeed the seed of a fruit. 
I think if I was you, I would purchase some coffee from a specialty coffee roaster (like: verve, ritual, 49 parallel, Intelligencia) and see if one of them really amazes you in any way, and then try and achieve that same roast profile. Other then that, don't always take those taste profiles to heart! They can certainly be different for anyone, and some often pretty silly. 

Good luck!