Yeah, try and make it on a day where you're usually home/not busy. Time of day doesn't matter; just try and keep it consistent to the same day of week every time you inject. It's just really up to whatever your schedule is that day. As long as you're not off by a full day or longer you're fine.
Even if you do accidentally miss a day, just take it as soon as possible and then take your next injection on the normal day.