"You'll be put in the hands of your stylists. You're not going to like what they do to you. But no matter what it is, don't resist."
When Prim is picked at the reaping Katniss at mediately calls as a volunteer to replace Prim showing her selflessness toward her sister, Katniss would sacrifice herself before she'd sacrifice Prim. As a hero, you need to be selfless and put you before others.
I most books or movies the heroines have some to give them advice, someone wiser than them that may have gone through the same thing or has magical abilities that will help in the future at some point like Dumbledore in Harry Potter. But in this case, Haymitch is the wiser someone that pieces of advice will help some point in the future will help Katniss.
A hero needs to have the perseverance when things were hard. Katniss kept moving forward, when her dad died her family was going to starve to death but she didn't give up or when Prim was called for the reaping Katniss would not give up protecting her sister.
A hero needs to be brave, Katniss is brave because she is not scared of the consequences the Capital has for breaking the rules for example when she goes hunting for food the consequence is like 20 lashes but she needs to feed her family so she does not care.
A hero needs to take risks because it might help them in the long run. Katniss took a risk when she shot at the game makers at her private audition wich help Katniss in the long run.
And lastly, a hero must have The Determination to have the willpower to do whatever is needed to get something done like to win The Hunger Games.