MOTM

Some of my modules have arrived and I am starting assembly.  Starting 
with the Power supply module first, there comes a step where it calls 
for heat shrink wrap tubing.   In the Power Supply instructions, Paul 
suggests using an Alpha Fitgun3.  I  cannot find much on the web 
about that product, but I do find lots of info on other brands of 
heat guns.  

Do I need a heat gun to shrink the tubing?  Can I use something else, 
like passing the soldering iron nearby?   Is there a cheap way of 
doing the heat shrinking?  Is there a lot of heat shrinking done in 
the other kits that would justify buying a quality heat gun?

Thanks for any help.
Andy Miller