Mid-autumn Festival

The Chinese traditional festival, Mid-autumn day is coming. It's one of the most important festivals to us. On that day all the family numbers will spend it together, it's means "reunion". In the daytime  (or - during the day) we will visit our relatives and friends. In the evening we will eat mooncake while watching the moon. It's a very beatiful feeling.

But there are some people who can not back spend the day with their family due to they are their work or study schedules outside. They will celebrate it with in a different way. Just like our company, which will hold an activity on that day. We will have a lot of programs and awards and  in order to have a good performance now we are preparing for it now. I am looking forward to the coming day.  Expecting the day coming.^^

Good -

If you are talking about a specific plan in the future then use "will'.  If you are talking about what you do on  a certain kind of day (holiday, festival, etc.) then use the present tense.  Since you started the entry talking about a certain holiday I took out the "will"s.  If you really meant to say what you plan to do this holiday then the "will"s can be left in.

We usually use  the preposition "on" for a specific day and  "in" for a general day. 

On that day we went to school.  In the day we usually work hard.  same with morning evening and night.  

On that night it was cold, In the morning we usually get up early

"Looking forward to" is the most common idiom to say that something good is going to happen and  you are excited about it.  I am looking forward to my trip.  I am looking forward to seeing you again.