Guardian traits
Try to get the gold. It’s not that hard, I got it without even trying.
Then just invest in the traits that fit your playstyle. Making builds in Guild Wars 2 is pretty easy and it’s hard to make actual mistakes, unless you’re trying.
I’m not wild about the Radiance traits, but the other four are all good in various builds and situations.
Like Ynna said, invest in the advanced trait book. How short on silver are you?
If you have no idea what your playstyle is, or you want to experiment, try 15 Radiance 5 Virtues. It’s an easy, flexible beginner’s build that refreshes Virtue of Justice every time you kill an enemy. It’s a strong ‘entry-level’ way on seeing how Trait synergy can change your playstyle, and it rewards you for paying attention to the fight.
I’m not wild about the Radiance traits, but the other four are all good in various builds and situations.
Radiance is amazing for offensively-minded builds, often better than Zeal, especially if you like 1H weapons; Right-Handed Strength is incredibly powerful.
@OP: I recommend messing around with a skill calculator like the one here: http://www.guildhead.com/skill-calc#Mcc. This will give you a better idea of what possibilities exist and allow you to experiment with ideas on paper without wasting hard-earned money on respeccing. Some things you will have to learn from experience, but you can at least see some of the synergies between the different lines.
As far as making money for your training manuals, make sure you are hitting all of the resource nodes that aren’t too far from your paths of travel, and if you aren’t using something for crafting, sell it on the Trading Post! Furthermore, try to avoid using fast-travel too often, as the price really adds up and causes you to skip many of the aforementioned crafting resources.