It is also helpful to (a) have the garment stretched tight in some fashion while blowing out ink, and (b) use a blow dryer on low and dry the area as you go. The tension on the fabric seemed to make the whole process easier for me when I was put in the unenviable position of blowing out the entire front design on 14 Under Armour black hoodies(the price tag said $75.00) years back. By the third one, I had it pretty much figured out and only lost one in the end...with the whole process using a little over 1.5 gallons of spot remover fluid and about 20 minutes per garment.
Also, you should know that the different fluids on the market are very much differing in their quality. Some even come with a lubricating element in them intended to improve gun life, but in my experience those tend to give you more rings.