How can I make my summer vacation more meaningful?

In fact ,at the beginning of the holiday I traveled to Thailand and I had a good time in there for ten days.
But,I had allergic rhinitis since I backed home. 
I'm very unhappy those day.
However,I know I should cheer up and I will be healthy sooner or later.
I believe I can.
Now, it will be half month before the new term starts, so it would be better for me to have a good plan carefully.
Do you know what makes my vacation more interesting and meaningful?

'In fact ,at the beginning of the holiday . . '         At the start of the holiday . .

' . a good time in there . '       a good time there

'But,I had allergic rhinitis since I backed home.'      However, I had allergic rhinitis when/after I returned home           'So painful it is!'        How painful it is ! / So much pain !

'I'm very unhappy those day.'       I was very unhappy (at that time)

IF IN PRESENT THEN :   I am (now) very unhappy (because of this)

'it will be half month'    it will be two weeks   [we don't say 'a half month' or 'half a month']

'to have a good plan carefully.'        to have a good plan / to plan carefully / to make a (careful) plan

'Do you know what makes my vacation more interesting and meaningful?'

Do you know how to make my vacation . . ?    /    Do you know what would make my vacation . . ?

How can I make my summer vacation more meaningful?

In fact At the beginning start of the holiday my summer vacation  I traveled to Thailand and I had a good time in there for ten days.
But,I had allergic rhinitis reactio since after I return backed home.So painful it is It was extremely painful!
I'm very unhappy those day I was in a very bad mood.
However, I know I should cheer up and I will be healthy sooner or later because I know I will get better sooner or later. 
I believe I can.
Now, it will be half month before the new term starts,The new term will start in half a month so it would be better for me to get ready and plan my schedule accordingly. have a good plan carefully.

Do you know what makes my how I can make my vacation more interesting and meaningful?

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