What would you have done?

[Zebedee]

More discipline in the orc army. None of this nonsense about various units killing each other off.
Also, not clear the steps to Mount Doom, make it harder to climb.
Perhaps make use of the barrow wights to attack the Shire.

[gorthaur_cruel]

I would've made mithril armor for my Nazguls, first of all. Sauron had a wealth of mithril:

Of what they brought to light the Orcs have gathered nearly all, and given it in tribute to Sauron, who covets it

Mithril armor would've meant that Merry's knife wouldn't have pierced the Witch King.

Also, let's face it: would you guys really have concentrated more on defending Mordor? You've got all the entrances into Mordor covered: Minas Morgul's defended by thousands of Orcs. The Black Gate's defended by thousands of Orcs. Cirith Ungol's defended by Shelob (whom nobody ever got past yet) and Orcs. He knows the limit of the armies against him. Why should he go on to strengthen his defences more when there was clearly nobody strong enough to attack him? I think Sauron didn't have much flaws in his strategy. His "mistakes" are natural mistakes, IMO.

[Elessar Telcontar]

I would have not given in to temptation and pride by emptying Mordor against the newly arisen King of Gondor. Surely emptying his his lands when the ring had yet to be found was foolish especially considering he knew it was not in the hands of Elessar, Gandalf etc.
In many ways Sauron caused his own demise by allowing himself to be fooled into letting his armies go into open battle at the Black Gate. In short Sauron should have believed his own weaknesses and ignored his pride...

[Gothbogg the Ripper]

I certainly agree with that, his pride did cloud his judgement when he sent out his army to face Aragorn and the others at the Black Gate, if he didn't do this it could have turned out very different.

[samwise8504]

i would of prevented smaug from been slain and made more use of him e.g. promise him more gold or land and watch him destroy gondor and rohan with ease.

[Essex]

Sauron should have not been so single minded. He didn't believe anyone would want to destory the ring, he would never believe anyone would have the audacity and stupidity to creep into mordor, and, most importantly, he was too single mided when torturing Gollum. As stated in unfinished tales, the Hunt for the Ring section, Sauron assumed that te shire was an area near to where gollum lived. If he had put thought into it, and got more information out of Gollum, it would have been Game Over. As Tolkien states:

"This was a very small and natural error – but possibly the most important mistake that Sauron made in the whole affair. But for it, the Black Riders would have reached the Shire weeks sooner."

[rutslegolas]

Yes I agree ,but the Dark Lord had reason to believe that no would destroy the ring ,he thought no one in their right state of mind would destroy the ring which could give a man ultimate power.

I think the Dark Lord should have fortified Mount Doom ,as he fortified the Black Gate.