Though the compering is pretty much a contextual job, there is something general about it as well. Taking care of these things and adding some lines below might help you.

1. Maintain a light smiling posture. Not the wide smile.
2. If you are not going to memorize the script, you will have to look into the paper on the dais time and again. Therefore, at least revise the script 5-6 times so that you become fluent in it.
3. Confidence - the Key!


Now here are some starting lines...

Bismillah e Rehman i Raheem,

Ladies and Gentlemen,

I Mr./Miss (your name) (add your class or distinction if any), on behalf of (Name of your institution) welcome all the distinguished guests here at this auspicious gathering in the colourful evening.

[Traditionally, we call someone for Qirat and/or Translation for formally commencing the programme.]

Let us commence our today's programme with the recitation of Holy verses from the Holy Book of Allah, who is the Lord of all the lords, the Creator of this universe, the omnipotent and the most merciful. I would request (name of the person chosen for recitation) to please come over the dais and recite the Holy verses.

I hope it helps.

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Verily, His command, when He intends a thing, is only that He says "Be!" - and it is! (Al-Quran)