In general it is not a good idea to lead from a random honor such as Kxxx, Qxxx or Jxxx (exceptions are when the auction calls for it). It is much better to lead a doubleton or singleton if you have one, but otherwise leads from passive holdings are fine, such as three small (the club suit)
"there is no reason to think diamonds are our suit" - these type of leads give away more than they gain.
The most important signals
Double or bid?
Bid as high as possible!
Defending against a multi 2♦
Transfer or not?
Nv compete
How strong vulnerable?
Preempt suit quality
6322 and 7222
2♣ opening
Doubleton lead
Passive lead
When to lead active
1N with 5422
Takeout double
Negative double
Splinters
Competing partscore
Try not double
Ace Ace King
2 level overcall
Lead Trumps #1
Lead Trumps #2
7 card GOOD suit
To open or not, pre-empt or not
Let the opponents play when they are misfitting
The strongest hand
Be practical