Hiding is the foundation, not the obstacle
A shy kitten who can retreat to a covered box, a blanket-draped crate or the space behind a chair has a base to explore from, and kittens with secure bases venture out sooner than kittens whose hiding spots are constantly disturbed. Resist the urge to drag her out for cuddles or to show guests; being extracted teaches her that nowhere is safe and that people are the source of the danger. Instead, make the area around the hiding place rewarding, with meals, treats and quiet company appearing there, so the boundary of her safe zone gradually expands outward on its own as good experiences accumulate at its edges.
Be boring, nearby and predictable
Sit on the floor near, but not facing, the hiding place, and read or work quietly so your presence becomes background. Direct staring, reaching and looming over a kitten all read as threats to a shy animal, while a person absorbed in something else is easy to study. Let her make every approach, and when she does, keep your movements slow and your voice low, offering a treat placed on the floor between you rather than held out in a hand she must brave. Short, frequent sessions of this kind build trust faster than one long attempt, and ending while she is still relaxed leaves her with a good final memory of you.
Play is the shy kitten's bridge
Many kittens who will not approach a hand will chase a feather on a long wand, because play overrides caution at a safe distance. Use the longest toy you have, move it in small, prey-like darts along the floor rather than swooping it overhead, and let her catch it often. Play sessions build a positive association with you as the source of the game, exercise a kitten who otherwise spends the day tensely still, and reveal her personality gradually. As confidence grows over days, shorten the distance inch by inch, always letting her set the rate, and finish games near a treat so play and feeding reinforce each other.
Expand the world one variable at a time
Once she is relaxed with you in her base room, broaden her world slowly: a new person sitting quietly with a book, a household sound played or occurring at low level, a second room explored with her safe carrier available as a retreat. Change one thing at a time so you can tell what she found hard, and return to the last easy stage for a day if she stops eating, hides continuously again, or startles at things she had accepted. Shyness that arrives suddenly in a previously confident kitten, or shyness paired with appetite loss or hiding from everyone including familiar people, should be checked by a veterinarian rather than treated as temperament alone.
Progress in inches is still progress
Keep a simple note of milestones, such as first voluntary approach, first play session, first time eating with a visitor present, because shy kittens improve so gradually that owners often miss how far they have come and lose heart at exactly the wrong moment. Celebrate the inches and resist comparing her to a bold littermate; their timelines are supposed to differ. KinsLe's Kinny can help you judge the next small step when you describe what your kitten did today, and keeping those observations with her profile means her confidence story is recorded rather than left to memory.