I get a lot of calls relating to tuning. The most common is that when someone try's to tune their harp to a tuner  all the note are out from what the manufacturer's say they should be. There are charts on the web that most of use that show notes = /- certain numbers ie blow hole 1 =0 , blow hole 2 = -12. These numbers refer to the relating note being in this instance blow 2 note being 12 cents flatter than hole 1 etc .  Now here is the thing you need to consider . The reference tuning of YOUR HARP will be unique to your harp. The way you play, ie hard or soft, the temperature ,the moisture etc all effect the tuning.  Most tuners will talk about a harp being set to 442hz . you harp may not. BUT dont be concerned. You need to go through your harp and establish ITS tuning reference . then write it on the top of your harp. It maybe that your harp is set to 442.5 or 443 or 441.8. all these tuning references are ok .The important thing is that the individual note are set relative to EACH OTHER. This is the most important thing. In my method outlined below you can with a little practice understand and establish what reference tuning individual harp is set at and then ONLY ADJUST the notes that require tuning. NOT ALL THE NOTE..       I have attached some pdf files so you can download them and print them to use  yourself. So go practice and establish the reference tuning of your harp.