# Reading number of outer shell electrons and other properties from periodic table?

How can one read from the periodic table the number of outer shell electrons that an atom has, to predict how these atoms will make bonds with other atoms? For example to see that hydrogen ($\ce{H}$) has 1 electron free, while carbon ($\ce{C}$) has 4 and oxygen ($\ce{O}$) has 2? This allows us to infer that carbon can make four bonds with 4 different hydrogen atoms. It's not clear what in the periodic table would tell us this; it is neither in the group nor in the period of an atom, it seems.

Related to this: can someone summarize concisely all the properties (like number of free outer shell electrons) that one can read off about each element from its position in the periodic table? I was having a hard time finding a concise summary of these.