How to select a spot color and send it to printer?

Dear Sir/Madam:

I really need your help on use a spot to print. I am a newbie on EPS.

I define a spot color as following:

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%%DocumentCustomColors: (Spot8)

%%+ (Spot7)

%%+ (Spot6)

%%+ (Spot5)

%%+ (Spot4)

%%+ (Spot3)

%%+ (Spot2)

%%+ (Spot1)

%%CMYKCustomColor: 0 1 1 0.1000 (Spot8)

%%+ 0.6000 0.8500 1 0 (Spot7)

%%+ 1 0 1 0.2000 (Spot6)

%%+ 1 0.2000 1 0.7000 (Spot5)

%%+ 0.8837 0.7692 0 0 (Spot4)

%%+ 0 0 0 1 (Spot3)

%%+ 0.8837 0.7692 0 0 (Spot2)

%%+ 0 0 0 1 (Spot1)

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How can I call spot color to fill a graphic and send it to printer?

I tried following and did not get any luck:

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  newpath

   0 0 100 0 360 arc

  closepath

(Spot2) fill

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The most important is to let printer know what spot color I am using.

Best regards,

James