There are some corrections, but your life still sounds pretty good!

Today was a good day

Everyday night when I lay on my bed, I prey to God and I thank him for another day, and tonight it won't be different.
I worked hard, had good food for dinner, studied a lot (math, a new programming language, english and others...), and talked to a sweet language partner on Skype. I think everything was good tonight until now. So far so good!
My day will be perfect if there are not many mistakes on that this entry.
Thank you for your corrections in advance.

Until now means that before now it was good, but now it has changed and is bad. We can use the expression so far so good, to express that you''ve had a good time and it's still good.

Partner - do you mean girlfriend? Or language partner?

Today was a good day

Everyday night when I lay on my bed (or: Every day before going to bed...) I pray <em>("prey" has a different meaning! It means animals which hunters chase down) </em>to God and I thank him for another day and tonight it won't be different.
I worked hard, had good food for dinner, studied a lot (Math, a new programming language, English and others...), talked to a sweet partner <em>(I would use a different word: a very nice/friendly language partner; or even "adorable" maybe, if the person was really that nice)</em> on Skype. I think everything was good tonight until now <em>(agree with Rebecca's correction: "So far so good!")</em>.
My day will be perfect if there are not many mistakes on in that this entry.
Thank you for the corrections in advance.