Where to start....
When you have a made hand. Shut down betting by betting high.
Yes, when you have a made hand don't let worse call you. Seems like good advice :/ or not.... While we want to extract maximum value at all times, we do not necessarily want to "shut out all betting". We should be sizing our bets based on our opponents range and either be charging them the most we feel they will pay with that range when we are ahead of its majority or the minimum that it would take to fold out that range when we may be behind. If we just bet people out of the pot every time we have a good hand then we are losing ALOT of value...
Only play hands AA, KK, QQ, JJ, Pocket 10s - 2s, Suited Connectors in late position 8/7+
Your range should be dictated by position, pre flop action, dynamic, image, players at the table, history with villain, stack sizes, tendencies etc.... Your losing money only playing the top 5% of hands. As a rough idea, around 15% should be tight enough yet loose enough to show a consistent profit. You can adjust this depending on skill, table dynamic and effective stack size. is Also if you have predominantly played online previously it is profitable to construct a limping range in live cash.
Fold any middle or low pairs you make on the flop..
This is totally situation dependant. There are all sorts of factors to consider here; number of players in the pot, position,
pot odds, implied odds, effective stack sizes,
equity vs villain range, tendencies etc etc. If you are always doing this your leaking money.
Don't chase a gut shot ever.
This, again, is not necessarily true... While it is correct we should not be passively chasing gutshots two streets, there are situations where we can use our equity to semi bluff, are getting the right price, we have combo draws, villain tendencies (ie. wil c bet flop a ton but then check give up turn often)....
Again.... dependent on soooooo many factors. We definitely can bluff and it can be quite profitable, but be selective in doing so. The better your hand reading ability and reading the easier this is to do.
Basically pretty poor advice all round....