"It was just another day."
"It was a typical day." (Typical - meaning normal. You could also say, "It was a normal day.")
"There was nothing special about today. "
You could use any of these expressions to talk about a normal, ordinary day.
"It was just another day."
（ありふれた一日でした）
"It was a typical day."
（典型的な一日でした）
"Typical" -典型的な、よくある、と言う意味になります。
また、次のように言い表すことも出来ます。
"It was a normal day."
（ふつうの一日でした）
"There was nothing special about today. "
（今日は特に何もない日でした）
これらの表現を使って平凡な普通の一日だったことを話すことが出来ます。
▪ Not bad or good.
This a short and sweet answer saying its not a bad day and its also not a good day.
▪ Its an average day.
This indicates that the day is half good and half bad.
▪ Not bad or good.（よくも悪くもない）
良くも悪くもない１日であることを端的に表すことができます。
▪ Its an average day.（普通の日）
良いも悪いも半々の１日であることを示します。
To say your day has been 'so-so' is to specifically say that the day was good, but also bad. You can use so-so for any situation that is good and bad.
When you say this you should hold out your hand infront of you at around chest-level, with your palm facing downward and your hand outstretched and flat, and then shake your hand a few times like this: dip you little finger down to the right and then do the same on the thumb side, dipping down to the left. This means your middle, longest finger is like the axis you rotate your hand around. Do this quite fast. This is the hand gesture we use to symbolise 'so-so'. (I can see that some helpful person has made a very short five second video on YouTube showing this, just type in 'so-so gesture').
Okay and alright can be used in this context to explain that you are not really happy and equally not really sad.
All of the above responses are casual and typical of the kind of reply you would get if asking about how the day is going. Obviously intonation is really important here. There is a great variation of the real meaning of these responses according to different intonation. For example, if you say, "So, so," in a happy way, it could mean that everything is going well as normal - and perhaps normal is very good for you! However if you say it in a depressed way, it could mean you have suffered some serious setback.
All of these responses are casual and means that your day was just okay- not good and not bad. You should just be mindful of how you say it. If ,for example, you say "It was fine!" in a cheerful way, it might indicate that it was great. If you say it with a straight-face and shrug of the shoulders, then it would be more believable as a just okay kind of day. Hope this helps!
My day has been okay so far, nothing to fancy/special happened.
Ive had a decent day, not a great day but not a bad one either.
If you would like to explain to someone that your day has been okay but nothing special, you can say something like "My day has been so-so, nothing bad but nothing special.". The phrase so-so is very common and a very casual thing that is said to express something being just "average" or "normal".
If you want to express that your day was not great but it was okay then you can use any of the sentences above.
If something is "Okay" then it is neither really good nor really bad.
Example sentences:
A: How was your food?
B: It was okay, but the steak was over cooked.
A: How was your day?
B: It was okay, but it was long!
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