By providing all the info/documents they need. You can do so by going to Resolution Center in your Paypal. Or just give them a call, its easier than you think.
you should know the reason of this limiting . if you didn't do any mistake they just will ask you your ID and address location proof be-careful if you send them any not 100% right document they will limit your account forever
Why Limited? You didn't submitted the required documents? or you had so many chargebacks? The mail you the reason and they will never lift limit until you solve that issue.