DEFENDING : LEADS

"Defending is tough, Jim - real tough." Davy Crockett, King of the wild frontier, was taking time out from defending the Alamo to discuss his favourite game with Jim Bowie. "Sometimes you gotta have eyes in the back of yer head."
"You gotta see through the back o' those darn cards n' all, Davy," said Jim, carefully polishing his long weapon.
"The hardest bit," drawled Davy, "is the dang openin' lead. The helluva thing is you got no idea what's right."
"Uh, yeah, well…" interrupted Jim, "Though you do got the auction, Davy. You kin learn good from that. What the shapes of declarer's hand might be an' all sorts innneresting stuff like that."
"True words, Jim, true words indeed. Which is why you should always pay very close attention to an auction, even if you ain't involved in it. While they're bidding themselves stupid to their cosy little grand slam or whatever, you need to be startin' up a plan of attack even before the auction is over. Listen to it. Study the hell out of it. Git yerself all prepared and ready - then Bam! Attack!"
"Then you gotta make that choice - the Opening Lead." Jim grew serious. Davy's brow furrowed.
" That is why, Jim Bowie, you gotta learn, or at least be familiar with, the table of standard leads. Thataways, dang partner will at least, mebbe, have some dang idea of what yer doin' and why yer doin' it. 
First, decide from the auction and your holdings the best suit to lead. THEN, decide which card is "right":
1) Top of a sequence.
2) Top of a doubleton
3) Middle from 3 small (MUD)
4) 4th best -  FROM AN HONOUR!!!!!
5) 2nd best from rubbish
6) Bottom of 3 to an honour
You may still be leadin' blind in the pitch black to a deaf partner, but, hey - you tried…and you did the right thing."