Option 1 - The property that you are requesting someone not enter upon can be properly posted. This means posting a sign giving notice to anyone not to trespass upon your property. This method is a blanket trespass and not specific to a person. This sign must be posted in a conspicuous place so that the sign can be easily seen by all. If you have a large area of property, multiple signs may be needed.
Option 2 - You may send someone a notice of no trespassing through the mail. This notice must include at a minimum; the date issued, who is being trespassed, the address of the property you are requesting they not trespass upon, that you are requesting them not to enter upon or trespass on this property, and who the no trespass notice is from. To ensure the intended recipient receives this notice and to prove service, this no trespass notice should be mailed certified through the Post Office, signature upon delivery. You should also keep a duplicate copy of the notice sent for your records and keep the certified signature receipt with to no trespass notice.