Here are a collection of commonly used phrases with the words 手 and 足:
手が空く： Just like it reads, "hands are open," i.e., you are free, not doing anything.
手が離せない： Again, just like it reads, "can't take hands away." This is used when expressing that you are occupied with something and can't do anything else.
手が足りない： "Not enough hands," in the ranch hand sense, not enough people, workers.
手に汗を握る： "Gripping sweat in hand." It's a euphemism for "being on the edge of your seat.
手を抜く： "Remove hand," or in other words, "cut corners."
手がかかる： "Takes hands," meaning to "have one's hands full with some chore."
手も足も出ない： "Can't put out hands or feet." Used to express being at a loss for what to do.
足の踏み場もない： "Not even a place to put feet." Pretty self-explanatory. Nowhere to stand, in the literal sense.
足が棒になる： "Legs become a staff." In English, we'd probably say the opposite, "Legs got rubbery," or tired.
足を引っ張る： "Pull legs." No joking, this actually means to hold someone or something back from realizing its potential. To obstruct.