Do you mean everyday or every day? The addition of that space makes a big difference in the meaning, so pay attention and I’ll explain what each means.
Years ago, a television station I worked for had a slogan that included the phrase “every day.” It referred to the station’s constant, continual commitment to covering news and weather.
From time to time, my boss would hand me a script that featured that slogan somewhere in the copy, and said manager would write it as one word, “everyday.”
I quietly changed it every time, because I knew the single word version wasn’t what we meant.
Granted, only the announcer was going to see that particular error on a script page, but even so, we grammarians would prefer that not even one person see a mistake coming from us, and since I was always the one who forwarded the scripts to the announcer, no matter who wrote them, I just couldn’t help stepping in for the quick correction.
Here’s what they mean:
Everyday means commonplace or ordinary. Everyday is an adjective.
Every day means regularly, every single day. Every day tends to be an adverb in its usage.
If you do something every day, it’s an everyday activity. In that sentence, every day modifies the verb do, which makes it an adverb. Everyday modifies the noun activity, which makes it an adjective.
In that promo, our “everyday” commitment to keeping people informed meant we were out covering news every day.
Now that you know the difference between the two, here’s an easy way to help you decide which one you should use: substitute the phrase “each and every day.” If it makes sense, then you need the multiple-word version, every day. Someone might read the newspaper “each and every day,”  and those people would therefore read the newspaper “every day.”
If “each and every day” doesn’t make sense or sounds awkward, you know you need the single-word version, everyday. You wouldn’t refer to daily chores as “each and every day activities;”  you’d call them “everyday activities.”