Sometimes licking humans can be a deferential behavior - meaning that it is done in contexts in which the dog is being submissive to you. This is the type of licking that a young dog would do to an old dog - for example licking lips and around the ears.
In a few cases, the licking may be more pushy than deferential - my dog Levee used to lick my hand and as she did she rotated my hand by pushing it with her nose so she could lick between each and every finger. For these "pushy" dogs, it becomes a "friendly" type of dominance.
Licking can also be obsessive-compulsive (maybe Levee's pushy licking was a bit obsessive-compulsive); however, most obsessive-compulsive licking behavior concerns the dog licking himself - i.e. forming lick sores on a leg or foot.
Sometime a dog may lick if a person's skin tastes good - i.e. salty due to sweat or maybe because they just ate corn-on-the-cob and their hands smell and taste like butter.
Sounds like your dog's licking is a bit of a pushy behavior or licking due to the taste of your skin.
You may want to get a veterinarian check-up in case your dog is licking due to needing salt - it would help to bring in a urine sample.
If your dog is licking due to pushiness, then pulling away, verbally protesting, and attempting to avoid the licks without putting on the dog's leash to physically stop the licking will make it worse because the dog may view that her licking is soliciting this submissive behavior from you. Your dog may be licking to get you to act submissive and when you do act submissive, it reinforces the behavior.
Ways to get your dog to lick less:
1. Be less reactive when your dog licks you. Don't say anything or push your dog away. Since you are sitting, calmly stand up and ignore your dog. Make sure that your dog's licking behavior is not causing you to react so that your dog submits even more OR causing you to react submissively to your dog when he's being a pushy licker. When your dog licks you and you stand up, fold your arms and look at the ceiling to ignore your dog. Ignore for around 2 minutes and then sit down again and repeat by getting up as soon as your dog licks again. Do this until your dog is associating her licking with you totally ignoring him.
2. You can leave the leash on your dog when supervising her and when your dog licks you tell her matter of factly "no lick" . If he stops, verbally praise her calmly , but do not pet him. If he does not stop, repeat "no lick" and immediately give the leash a quick snap. Calmly praise him if she stops.
3. You could try to manage the licking - for example, when he is in the chair with you instead of giving him free access to your exposed legs, tether him near you so she cannot get to your legs. Or you can wear long pants so he cannot lick your legs.
4. Another thing you can do is to teach an incompatible behavior - a behavior that if your dog does, your dog cannot lick and do the behavior at the same time. For example, sit and wait are incompatible with your dog licking your legs.
5. Or you could teach a command for licking, such as "Kisses" and practice "Kisses" a lot until he is licking on the command of 'Kisses" and then just stop giving the kisses command. When he is licking on the command "kisses" (easy to teach by smearing a small amount of margarine on your hand), then teach "enough" by saying "enough" waiting for him to stop and then giving him a treat.
6. Or you could try a taste deterrent such as bitter apple on your legs. Then when he licks your legs, they will taste bad.
Hope this helps give you ideas to lessen his licking behavior.