The sticky roller is an interesting kind of product to get long hair from carpet.
Lots of hair on carpet.
Add several drops of fabric softener.
Fill a spray bottle with water.
If you are trying to remove long hair in your carpet you would want to use short deliberate strokes.
Use it by pulling it towards yourself.
Now roll it over your carpet.
It d be a lot of work for large areas though.
Brush the carpet with a stiff bristled brush or.
The sticky will pull the hair right out.
Hold like a regular broom but do not push.
Spray the carpet lightly to dampen the hair and prime it to clump together.
You can buy one or simply can make one yourself.
Longer more regular style sweeping will still collect some but for a better charge and deeper clean keep the movements short and firm.
It ll take a while to do the whole carpet like that but it balls up the hair and makes it easier to gather.
It works well on carpets.
For problem areas i tape together a square of masking tape about a foot 0 3 meters on a side and press that onto the carpet after a stiff brushing.
Use the dishwashing gloves that happyturtle suggested and rub your hands in a circle in one area on the carpet.
I have long hair that constantly mucks up my vacuum so i just take scissors to the hair after i ve unplugged the vacuum.