Social skills are, yknow, skills. Some people learn how to play guitar faster than others, some people learn how to skateboard faster than others, and some people learn how to make friends faster than others. You can read books on this stuff but at the end of the day the only way to get better at it is to get yourself into social situations. Which doesn't always mean getting yourself balls deep into the nearest block party, you can practice good communication habits on the forgetin' cashier next time you're at Walmart.
Don't expect to make friends with people you don't have stuff in common with. Most of your 'friends' you'll have throughout life are people you meet through hobbies, work or close communion. The rest are probably people you get stufffaced with at parties. Note that you don't always have to approach people to be friends with them, few of my friends are people that I sought out and approached, they're people who took interest in me at first. You just have to be good at conversation, you don't necessarily have to constantly seek out new friends.
