Multiple LED's with 74HC595 - Resistor Setup

hej guys,

i'm want control lot of led's 3 74hc595 shift registers. i'm wondering how connect them proper way. many installed seperately on seperate pins of register, planning put 11 led's on single pin, since turn them on , off together.

now i'm wondering kind of resistor setup have use, 11 led's on single pin.
my questions are:

1 - should put 11 led's in series, or should connect them parallell? can of those, or should never put lot of led's on single pin?
2 - , how should use resistors? 1 before of them enough? or need 1 before each led (which kinda makes no sense when in series.
3 - wondering if use single resistor of led's, before go ground. read somewhere shouldn't this. correct? save me lot of trouble if use 1 resistor ...
4 - else should out kind of setup?

thanks lot in advance suggestions

74hc595 should drive 1 led 8 ma of current. should drive 70ma of current total before part overstressed.
use atpic6b595 instead, can sink 150ma per output, have 11 leds in parallel, each current limit resistor, , 13ma of current each. or wire bunch in series 50v source , 20ma thru them all. tpic6b595 controlled same hc595, has low outputs - shift in 1, output goes low sink current thru led positive supply (vs sourcing current thru device gnd).
leds in parallel each need resistor.
leds in series need resistor each string of leds.

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