Many types of clocks exist on the market today, from mechanical clocks such as the grandfather clock or cuckoo clock, to quartz and electrical clocks. Atomic clocks use the frequency of absorption and emission of electromagnetic radiation to keep time. Despite the wide range of clocks, most clock hands are manufactured in the same manner and adjusting them is a quick fix requiring nothing more than your hands and a small pair of pliers.
Examine the hands of the clock to see if they are touching or caught on each other. If so, gently unhook the hands until they are free to move. You may need to gently bend the hour hand towards the dial to allow a free pass of the minute hand.
Check if the hands are touching the glass dial case--this will also impede movement. If so, gently bend the affected hands towards the number dial to disengage them from the glass.
Examine the clock hands to see if they are loose. If the hour hand is loose, use your thumbs to push it snugly into the stem of the clock. If the minute hand is loose, go to the next step.
Tighten the little nut on top of the minute hand with a small pair of needle-nosed pliers.
Examine the hands after tightening to ensure they are free from catching on each other or any obstructions. Gently bend them back into place, if needed.
Some minute hands are also press-on hands, like hour hands, and can be tightened by pushing them into the hub in the same manner as the hour hand. If tightening and repositioning the clock hands does not solve your problem, you more than likely have a gear or other internal clock problem.