When lauding yourself, your various successes and many virtues, always use superlatives, and always round up. When speaking of others, and especially of people who oppose you in any way shape or form, always load your language with negative connotations, and always round down.
Never pass up the chance to be the naysayer in the room, the discourager, but do so in the interest of what you call "being realistic." People should leave your presence with fewer dreams and less lofty goals than before they met you.
Our war against peace is going very well. We've convinced the enemy's followers that though they may rhetorically claim to serve the Prince of Peace (how the very name makes me retch!), that fact need have absolutely no effect on their daily life, let alone on their unquestioning support for their nation's wars. The Prince of Darkness, I am happy to report, is very pleased with our work on this front.
In a similar vein, the P of D is also pleased with how we've managed to confuse the enemy's followers into conflating nationalist pride (which they call "love of country") with love of, well, the enemy himself. Over the centuries we've got them so used to thinking of God and country as an inseparable tandem that now they can't think of God at all apart from country. Again, good work, my legions.