Changing the serpentine belt with out an air

That isn't the way to do it. You should have a bypass pulley, which keeps the route and the angles and the same length belt.

Details of bypass and the serpentine belt diagram in the link

https://www.google.com/search?q=2006+Nissan+Altima.+Serpentine+belt+diagram+no+air+conditioning&tbm=isch&ved=2ahUKEwiT2pXX38H0AhWQsHIEHZE8ARMQ2-cCegQIABAA&oq=2006+Nissan+Altima.+Serpentine+belt+diagram+no+air+conditioning&gs_lcp=CgNpbWcQAzoHCCMQ7wMQJ1CQGliJTmC4aWgBcAB4AIABa4gBnwiSAQQxMi4xmAEAoAEBqgELZ3dzLXdpei1pbWfAAQE&sclient=img&ei=0femYdOtEpDhytMPkfmEmAE&bih=937&biw=1920&rlz=1C1QJDB_enCA643CA644

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Without the compressor, don't you need to put a different pulley in its place in order to reuse your existing serpentine belt? I'd read what these guys have to say before going any further:

http://www.wranglerforum.com/f218/deleting-air-conditioner-1993890.html%3famp=1

Is there any particular reason why you want to eliminate your compressor? If you don't turn on the air, the compressor freewheels, so why bother removing it?

The picture is for a zetec. Let me know if wrong diagram?

Should be a diagram on hood.or at radiator .

if the serpentine belt is original then have it changed as it is probably hard and not gripping properly
it is a reason that the ac compressor will not be at full efficiency , just like power steering not as good as it should be and alternator not charging properly
the inspection of the belt is in the grooved section and it shows minute cracks in the groove ribs then it is overdue for a change

Here is a copy of the serpentine diagram for your car. If you look at the second diagram it shows the location of the air conditioning compressor. The compressor will have to be one of the wheels for the serpentine belt. Not sure which engine you have. Here are the diagrams. Hope this helps.
http://www.2carpros.com/diagrams/chevrolet/beretta/1993

I would suggest that you have the A/C pump replaced. In the mean time you can remove the A/C belt, even if it's the entire serpentine belt and replace it with a shorter one to eliminate the A/C Compressor. If you go to your local parts store and ask for a belt for that model car they will ask if it has air conditioning or not, tell them that it does but you want the belt for the non air conditioned model and a mounting diagram. This will leave you with no air but in a short while the compressor is going to burn that belt off anyway.

If the air compressor is bad... check the diagram under the hood for the serpentine belt. Most vehicles will have a diagram that displays the serpentine belt path along with a part number for a shorter belt to bypass the ac compressor. If you can't find the diagram, go to your local parts store and they should be able to help.

This vehicle has one(1) belt a serpentine belt, this belt runs on all the pulleys on your vehicle . To change this belt is pretty simple there is a tensioner pulley that keeps belt tightly secured on all pulleys by eliminating that looseness. All you need depending on production dat is a 3/8 ratchet or in some applications a 15mm flat wrench. Look for tension I have provide you a diagram with the lay out of you belt .First Identify your system from the diagram before you proceed. Using ratchet/wrenchPull down or up which ever makes tension on belt loose and remove belt. Replace belt in the opposite of taking off following routing diagram. Good Luck contact if you need more help. Thanks for using FIX YA. http://www.2carpros.com/car_repair_information/tec_info/1999/gmc/sierra/1999_gmc_sierra_drive_belt_routing_diagram.htm

Here is a link to a picture of a 2002. Hope it's the same.

Serpentine Diagram