I go on exploring binges once every half a year or so to break up the monotony. As stated above, its best to have a fully skilled and well fit ship. When I go through wormholes I often go for several days at a time and concentrate on either relic or data sites but not both because I need the slots in my fits. I would go for 3-4 days at a time and log off mid space. Relic sites on average are more valuable, but data sites are OK too and like I said, break up the monotony.
Last bout I did was in a Tengu, fitted with Interdiction nullifier, Accelerated ejection bay, Covert reconfiguration and Obfuscation manifold for sub-systems. This is a very flexible fit, you have a cloak, built-in bubble immunity, you warp fast, and I ran it with 2 ECMs. You still have enough tank and DPS to deal with mid range rats and explosion damage relatively well and can GTFO fast when you need to. The drawbacks are that the high end explosions, radiation waves etc. can take you out so you can’t linger, have to warp out on those sites. I could of course get rid of teh ECM for tank, but then I’m actually more vulnreable to PvP which IMHO is the worse of the 2.
As far as systems go, I like to mix it up and travel through wormholes. I avoid systems that are most traveled, have most players in them either in space or docked as well as dead end systems. Dead end systems are usually quiet, but they also tend to be the biggest traps, because they are dead end systems.
When doing sites themselves, I like to do the ones that are well beyond D-Scan range of anything or at least furthest away, in range of least other places, be it asteroid belts planets moons, stations, whatever. You have a lot less chance being picked up if you are in range of only 1 or 2 places vs being with d-scan range of 5 places. Don’t forget you can use your in-game map to check for player activity of all sorts before you even jump into any given system. This helps out greatly as well.