Sorry if I'm late, but this worked for me when I had to dose my kitty alone.
Prep your meds beforehand, measured and ready to squirt.
Get a beach towel (a regular one might work for a kitten or small cat) and lay it on the floor.
Grab your cat and place it on the center of the towel so that the sides of the cat are parallel to the long edge of the towel.
Quickly fold the tail-side edge of the towel over your cat, pressing it down into a crouch and tucking its tail/legs in, and making sure that the fold is snug against the cat. This is important for thwarting the back-out. Kneel on top of the kitty package, one shin on either side of the cat, keeping its legs tucked into its sides with your legs.
Pick up medication with your dominant hand.
Bring your non-dominant arm down over the front paws and around your kitty's chest and cup its jaw with that hand. Use your thumb and finger only to put gentle but firm upward pressure on the corners of its mouth. You should be able to grip its upper jaw securely enough to prevent it from wrenching its head away. (Don't squeeze its throat!) This should irritate the cat into tilting its head upwards, and lifting its upper lip. You should see a gap behind its canines; insert syringe/eyedropper and squirt. If it tries to twist its head sideways, keep gently pushing upwards to 'reel in the slack'.
Hope this helps,