I wouldn't say that I'm a vegetarian, but I understand why people choose that lifestyle out of respect for sentient life.
Are there personal benefits why a person would become a vegetarian?
Because it is the absence of eating meat and so the abstentation of by products from slaughter, there are a few animal based problems you'd avoid. 
How can one become a better vegetarian?
Better vegetarian is tough to answer, but there are steps up from vegetarianism.  There's veganism, and they exclude all animal by products in addition to every vegetarian.  So no eggs or dairy.
Wow that seems difficult. What else can you tell me?
some (crazy) vegans even avoid animal product like beeswax and silk clothing.
It seems like a lot of work to constantly look at labels to see what is in a product.
Packaged and processed foods, such as cakes, cookies, candies, chocolate, yogurt, and marshmallows, often contain unfamiliar animal ingredients, and so may be a special concern for vegetarians due to the likelihood of such additives. Feelings among vegetarians may vary concerning these ingredients. Some vegetarians scrutinize product labels for animal-derived ingredients while others do not object to consuming cheese made with animal-derived rennet. Some vegetarians are unaware of animal-derived rennet being used in the production of cheese.
Semi-vegetarian diets
conscious of their behavior and have a choice; this is why there are laws governing human behavior, and why it is subject to moral standards.
Ethical vegetarian concerns have become more widespread in developed countries, particularly because of the spread of factory farming, more open and graphic documentation of what human meat-eating entails for the animal, and environmental consciousness. Some proponents of meat-eating argue that the current mass demand for meat has to be satisfied with a mass-production system, regardless of the welfare of animals