I practice pretty much everyday, even if it's only for half an hour - you get greater gains in your technique that way. I'm splitting my practice time between a couple of instruments right now so I have to be strict and have a good idea what I'm going to go through and that I touch on everything. For example I go through a warm up routine I got from a bass book which is great for strength and endurance, then I'll hit slap techniques for a while, going through riffs I've learned then finishing on the latest slap riff I'm currently learning. Then I'll move on to a Jazz bass solo I'm working on then play through some band numbers or riffs for a new song.