Just few days back had issues with my laptop keyboard (Lenovo Ideapad Y560p).
So here is simple How-to, hope it helps.. There is no universal repair guide because all keyboards are different.
Each key is held in place by key retainer (in my case blue clip), the back of key cap has 4 small clips. And below each key there is a rubber (silicon membrane). If your keyboard keys are getting stuck, clean around silicon membrane, that should fix it.
And finally, put the key cap on the retainer and snap the cap back in place
Order new keys