I wouldn't use human hair gels, they aren't tested for safety. Petsilk Topknot gel is perfect for this, and you only use it on the short hairs till it grows out. Here's a picture of it.
http://www.muttmart.com/mm5/graphics/00000001/PK122.jpg I found some on e-bay. You can usually put some sort of band and bow in by the age 3 months. This site has some great tips for putting the band in and getting puppy use to bows.
Casual Way to Put Dog Bows In