Write a review about a festival you have been to

Next weekend in on beach Samil beach, two musicians are organizing a large beneficent benefit concert: Festival Sand America. Money will be donated to an NGO for local children local ONG.
On Friday, we can see in concert a “luar na lubre” with his wonderful traditional sound.
On Saturday, the best day of the Festival, will play five different amazing groups will play. Four of them are local groups, with various kinds of music. But at about 10 hours o'clock, will play, surprisingly, “One Direction”, the preform more most anticipated performance.
On Sunday, will be children's day, because there will be children's attractions, such as inflatables, and at 6 hours o'clock will play “Cantajuegos” will play.
This will be a great large festival, and I hope that many people goes to the festival, because it is (or, in future tense, it will be) the best festival in this year, and the cause is wonderful.

Very good Isabel! My corrections are in red and my suggestions to sound more natural are in blue/grey.

ONG = NGO in English (non-governmental organization).

An inflatable = "bouncy castle" (UK) or "moon bounce" (US).

"But at about 10 hours o'clock, will play, surprisingly, “One Direction”, the preform more most anticipated performance." - A more natural-sounding way to say this would be:

"But around 10 o'clock, surprisingly, "One Direction" will play the most anticipated performance".