Here's a link with ideas for you:
Lights with tiny lightbulbs and fine gauge flexible wires are known as fairy lights (first picture below). They are usually battery operated. Keep in mind that battery operated string lights, even if LED, will eat batteries like crazy. Either purchase rechargeable batteries or go with the larger mini lights.
Mini lights (second picture ) have larger lightbulbs than fairy lights, and heavier, less flexible wiring, but are usually operated by being plugged in. Mini lights are available in a variety of string lengths and number of lightbulbs pr string.
Fire place mantle on stair railings windows
Wrap them around your christmas decor, in garland, or put them on furniture. Have fun!