With most of the injectables I don’t think it makes a difference. I usually do mine right after I get out of the shower, that way I know the injections site is as clean as possible. (still use alcohol swabs).
For Orals try to split them up throughout the day to keep the doseages as level as possible. (ie. if you’re taking 8 5mg Dbol tabs, take one every 1 1/2 hours or so.)