Some ways that you would be able to target a person with sigil effects would be:

• Draw the sigil on, or around a picture of that target.
• Draw the sigil on, or around the name of the target.
• Draw the sigil on, or around something the target is associated with.
• Use the targets name in the intention of the sigil.
• Places the sigil in an area where the target frequents.
• Allow the sigil to make physical contact with the target.
• Place the sigil in an area where the target will see it.
• During the charging and activating process focuse intently upon the person you want it to affect.

These things can be done with pretty much any type of sigils, and would be a very important thing to remember if you ever have to cast a sigil on to someone. Some of these you may need to charge, and activate the sigil beforehand in order to target them, and others will be done before the charging and activating process.