I cannot comment on drop shot as I do not fish it much but for Ned’s, the depth of the water is going to dictate the weight of the Ned head. For 0-15 ft, I use 1/8 to 3/16 ounce. As much as I hate to say it, choosing the right color will improve your bite. I am a PB&J fan for the waters I fish, the waters you fish may be different so experimenting is key.
After casting, let it sink to the bottom on slack line. A straight down sink is important as many fish will strike it on the fall. When bringing it in, use small jerks on slack line, slack line is very important, make sure there is a bow in that line. You want to try and make it seem that the bait is a minnow eating something off of the bottom every 4” or so.
Like a jig, feel it out. If you’re in rock, perfect. If you’re in mud, you’re probably not going to get bit.