Bad Tip # 1: Sweat out your cold
With this tip, people are typically referring to getting out there on the bike and working through the cold. I cannot recommend against this enough. Dehydrating yourself is literally the opposite of what most people recommend. This might be what they recommended years ago, but not now.
Bad Tip # 2: Train in the 53 x 11 uphill until you reach a standstill
While low cadence intervals are quite certainly a thing, the cadence required for this exercise is sub 30 RPM and is spelling disaster for your knees.
Bad Tip # 3: Don't drink anything on a long ride
You will get no training benefit out of this. This is stupid.
Bad Tip # 4: Start out your climbs as hard as you can
If you want to minimize the amount of time you spend in your zone (which is not what most coaches recommend) then do this. If you start out too hard, the rest of the climb will be absolutely miserable.
Bad Tip # 5: Slam your stem
Yep, slammed stems look cool. But a low stem is something you need to work up to. If you want to get more aero on the bike, try making very small increments. Take out one spacer every month or so until you reach the desired height.
Bad Tip #6 Carbo Load the night before an event
There may be some situations where you want to have carbohydrates in your diet but loading your belly full of past and going to bed is not the best way to get good rest.