The kits that I worked with had a tool for punching the hole to accommodate the barbed fittings. But it was always a very tight fit and wore out my thumb and index finger. I avoided the use of any product that would possibly cause the fitting to pop out; or react with the tubing and weaken it. Mechanical aids like pliers can work but every so often they slip and then I really appreciated the value and convenience of 'goof plugs'.

I'm a grown man and have great difficulty with some types of tubing---I have to use a pair of pliers to get it done. Try your local irrigation supply house -- they have a VINYL tubing that is much, much easier to work with than the hard stuff. Keep up the good work!!!