Tip 6: Change your tire with a knife (multiple tubes necessary)

Those bike shops are always reaching deeper into your pockets. You go in to buy a handful of spokey-dokes, and you come out with a french-made, full carbon bottle cage that costs as much as your bike.
The worst is the things they put on the counter to tempt you: Patch repair kits that cost more per gram than truffles, and those tyre levers - which are just bits of moulded plastic - for $29.  You won't fall into that trap!
And then it's time to change that tube, so you go into the kitchen and find the bluntest looking butter knife. The risks here, as you put the tyre back on over that virgin tube, are evident, so you exercise extreme caution.
Pump it up, and listen.
Fssssssssssssssssss.

BONUS TIP: When you go to the shop to buy a half-dozen replacement tubes, accept that your pride won't let you spring for the tyre levers just yet.