I really like to play bruiser characters, and I realize that part of my purpose is to carry other players, but I feel like I am always getting behind in CS and therefore behind in the games. Sometimes it's because the person I'm laning with keeps last hitting all of the minions I intend to (which by the way is really annoying. You can kill your own minions, thanks. :l) but a lot of the time I think it's because the characters I am picking are not that great for farming minions. Let's have a look:

Shen: Ki Strike helps, but I get most of my last hits with Vorpal Blade. It's decent once you level it up, but until then it can be tricky to time things right (for me anyway). First I like to get my boots out of the way, then prioritize some health, and then add some attack speed (you obviously can't be too tanky or else they will just ignore you).

Rammus: He can last hit a group of minions with power ball, and if he's tanking them all he can kill them with his defensive stance, and after level 6 he can use tremors to farm because of its low cool down time. You'd think I would have a better time with him, but it's still meh (unfortunately it also seems that Rammus gets banned a lot).

Nautilus: Unfortunately I don't own him yet, but he's really fun and his riptide is good for minion farming combined with Titan's Wrath. Easy to play him as AP too unlike Shen. I also just get so much enjoyment out of using Dredge Line during chases. Hopefully my judgements in the Tribunal will help me get along up there to 6300.

Singed: Things just clicked with him for me. I played him well since the start, but farming still starts off slowly for me. Until you level up the poison trail the chance of you getting a last hit with it is pretty low with other minions around and using your shield tends to be the best way.

Malphite: Seems like the best way to get CS is to use the seismic shard at the beginning. Damage is decent and you don't have to be that close to the creeps. Later on I like farming with his brutal spikes buff as the splash damage usually lands me more kills. Still trying to figure out what to emphasize with him to make him more threatening.

Since most people usually want to play the roles that get the kills I am well-liked during team fights, but if I'm behind in gold farmed then my items are not as good, so I am not as great of an asset as I could be. Of course other times my team gives the enemies just enough kills to make them unstoppable (a lot of times) and I can't do anything about it anyway or they don't work as well with me as they could.

Before you answer:

Yes I know about "S" and "H." It's just that waiting around usually gets me harassed more than anything. I've read that pacing helps, but since I am not attacking them that gives the enemy more time to come harass me before I can kill the creep.

Rammus and Naut are better in the jungle than top. The others you've mentioned can all farm very well as long as they're not hard countered. You have to know how to win trades or sustain faster than them; if you're dealing more damage to them than you incur, eventually they will be too low to contest the lane and have to back off, and then you can zone them out of gold/xp. If you sustain well, then you can get some extra CS and take a bit of harass because you'll be back at full health soon enough.

small nautilus tip: there are certain walls (well, more like cliffs) that you can dredge line over by hitting the real wall on the other side. the ones that you can do this to are pretty obvious--they're hardly a wall at all, and they only consist of a terrain height increase

Well I've been practicing with them in bot matches, which could be why. I mean bots totally ignore creeps and harass you because "Hey, we'll get items over time anyway so it doesn't matter."

if you are using skills aside from singed poison and shen vorpal blade for last hits on that list you are doing it wrong, you should be tanky enough to withstand trades, shen can win most of his since healing from q

malph after a few levels can clear waves with his w>e combo to help push fast then leave his lane

naut and rammus aren't top laners

Not to dissuade you from using any of those champions (they are all viable), but if you're having an issue with last hitting out of top lane, perhaps consider Irelia? Her Q is a last hitter's dream.

Unless you are using someone like Nassus, there is no reason you should be last hitting with your abilities. All you end up doing is pushing the lane and draining your mana.

Naut top is only a good counter for GP. I rarely found him to be an actual good top champion. you can play him as support, but he's iffy

Ive seen guides elsewhere that suggest making a custom game with a mirror character and seeing how fast you can get to 100 farm