When fishing swimbaits it is important to know a few things. First, what kind of 'swimbait' are you using. Just like Mattlures said, there are paddle tails and then there are swimbaits. When I was growing up we differenciated by calling one a paddle tail grub and the other a swimbait. So now we have the terms aside, we can focus on how and where to use swimbaits.
For the most part you want clear to mildly stained water. They will work everywhere there are fish, but why spend the money on the bait and equipment if the bass aren't picky about realism due to lack of visability? That's a common sense thing.
Next, you have found your clear to mildly clear water now to present the bait to the fish. First off use a swimbait wherever the fish are holding. The thicker the cover will dictate the type of bait you are using. I first got hooked on Castaic back in the day when they were almost the only swimbait manufacturers out there. I still like em, but there is one problem. They usually have a treble hook exposed with no bill to deflect off of cover, meaning guaranteed snags here in Va (I learned the swimbait in Deep/Clear Arizona Reservoirs with nothing compared to here as far as cover where snags weren't really an issue). So if you have heavy cover with clear water, I would not go with the hollow bellies. They're not realistic enough, so I would go with the Sebile Soft Magic Swimmer. It comes with the terminal tackle to rig it weedless and swims like the magic swimmer. Through grass it is awesome. Still focusing on the basics, weedlines, transition points, pockets, etc... Think crankbait/spinnerbait.
Now, another variable to be considered is the toothy critters that may or may not inhabit your waters. I lost three Catch 22 swimbaits from Castaic in one day when I first started fishing Va to Gar tearing them apart, and at $20 a pop that was the end of using Catch 22's. I had fairly open water adjacent to the docks I was fishing so snagging wasn't a thing. So I then got their Rock Hard series of trouts. Now a lot of people gave me flack for that because in my brackish water there are no trout. So? A fish is a fish and can be eaten by anything anwhere. I could take that little Rainbow Trout immitation and fish salt water with it and do well with Speckled Trout, if a fish is hungry and something swims by it doesn't take time to discern if its a type of fish that's natural to its waters. I mean seriously how many Rage Tail Hawgs or Shads have you seen swimming around, or wooly bugs or Mega Bugs? If it looks alive they will eat it.
Now the presentation can vary greatly. During peak feeding times is when to use the big swimbaits in a slow retrieve through feeding areas, going back to the transition points, dropoffs, points, so on and so forth. But there is the non feeding times too that you want, or need to put fish in the boat. This is where I downsize my hard swimbaits and use a spinning rod with braid and a short Flouro leader. I will go to the 4in Rock Hard Baby Trout and work for a strike. I say rock hard because when the following presentation is applied the body will click against itself at the joints. I will cast out, and much like a sinking jerkbait, jerk the lure back in. Less pauses for more active fish. In fact during the summertime I won't pause at all. Reeling and jerking all the way back to the boat imitates a stressed and violently injured baitfish. If you get a chance do this next to the boat or in a pool and you will see what I mean. This is how you can turn you hard finesse swimbaits into a reaction bait. Look at youtube and search for a pike grabbing a bass that is fighting an angler. It's the same concept. Or why does a shark attack a fish that is on a line when it probably would have left it alone if it weren't?
Equiptment is a different beast all together. For the large 2-3oz 10"-14" swimbaits you need some serious gear. I would say a 7'6" to 8' Heavy to Extra heavy rod with a fast tip (remember most swimbaits have trebles that you don't want to power out of the fishes' mouths). I don't use anything that big anymore and a 7'-7'6" MH FT rod is good for me. For the finesse stuff I am using a 6'6" Medium spinning rod.
Line, generally think Flourocarbon in the heaviest line you can get away with. In some clear water that would only be 10-12# test. If your targeting in low light (remember peak feeding times + areas) then 17-20# flouro is workable. Adding scent is almost a must, make it walk, talk and smell like a duck and the hunter is going to shoot it (metaphor people). My braid/flouro combo I use is 20# spiderwire with 17# Stren Flouro.
Last comes patience. Most guys who catch MONSTER bass out west with oversized swimbaits are usually coming in with only a few bites a day. Big swimbaits aren't a numbers catcher because they have very little to do with reaction and everything to do with hunger. You will see a lot of followers and that gets disheartening. One thing to mention about that. If you are in a slow retrieve and you see a follower, twitch the bait. It will turn around and then you pause the retrieve. Many times this will trigger the follower to strike.
I hope this helps. As far as this all goes it has been years since I have been in a place where swimbaits are super useful. Like I said, why spend money on realism when you're throwing into dirty water. The fish can't see it very well anyways. Any new tactics or techniques that have been introduced since I learned the baits, I am all ears. The Corps will probably take me back to California anyways.
