effortlessly

effortlessly
    adv 1: without effort or apparent effort; "she danced gracefully
           and effortlessly"; "swallows gliding effortlessly through
           the air"
    

21 Moby Thesaurus words for "effortlessly":
      adeptly, adroitly, easily, efficiently, expertly, facilely, freely,
      hands down, lightly, like clockwork, like nothing, no sweat,
      on easy terms, proficiently, readily, simply, skillfully, smoothly,
      swimmingly, well, without difficulty