Timidly is the adverb: doing something in a way that shows you are frightened or unsure of yourself. It nearly always sits next to a small, quiet action verb — she knocked timidly, he asked timidly, they timidly raised a hand, she smiled timidly. That is what makes it useful in storytelling: 'She asked' tells you nothing, but 'She asked timidly' shows you her voice going small. Writers of novels use it constantly for exactly this reason, and it can start to sound overdone if you use it twice on the same page. Like the adjective, it also stretches to decisions and money: 'the company moved timidly into the new market' means they went in too carefully, and the writer thinks that was a mistake. Position is flexible — before the verb or after the whole phrase both work ('he timidly opened the door' / 'he opened the door timidly') — and the meaning does not change. Its close relatives are 'nervously', which is about the feeling inside, and 'hesitantly', which is about pausing before you act. Timidly is about the smallness of the action itself.