How to attach crochet parts ?

Hello there ,

i made a big flat circle as a bear face , and two other small circles , i would love to attach the ears to the head but every time i bick up the  head while the parts are attached , the ears kind of full down and it obvious that they are attached ,i want to attach them very neatly cause i tried with rabbit ears and its the same i fail at this part .

so i want to make them sepretly but attach them as if i they are made togather , like if there a stitch attach them togather and neatly rather then slip stitch cause its make the ears flubbly , and single crochet is too much obvious , if there is a way to avoid this plaese help me with a stitch or pteern a video or anything else  !!