Leads/Melodys/Bass/Subbass?

[Tantalus]

I have a really hard time with all of the things listed in the title, Can I get some advice and general tips and tricks to making all of those things? Preforably in the house-y trancy style.
Please and Thanks!

EDIT: I should have been more clear in the original post, Sorry about that.

http://soundcloud.com/tantalusmusic/awoken-house-remix-wip
For example purposes. It's really WIP, and I think it sounds like shit. (ITS SO EMPTY ;~;)

1. Leads
I have such a hard time coming up with a lead, Whats it suppose to sound like? What goes into making it? Where does it go in a song?

2. Melodies
Same as above: What goes into make them, What are they supposed to sound like etc

3. Bass
Jesus, Everyone tells me bass is simple and easy, but I have a hard time with it. Again, What goes into making it, what separates it from subbass?

4. Subbass
Same as bass, only flipped around at the "What separates it from subbass" part.

I know a song needs all of these things, I just happen to suck ass at making all of them. Without them, my song sounds empty. How should all of those things sound in a house song? Questions! Questions everywhere!

[Lavender_Harmony]

You need to be less vague, perhaps post some of your material so we have some sort of base-line, a place to start from. Your question is essentially 'How do I write music', and I don't think anyone can answer that clearly, fully and in a helpful manner without prior context..

[Captain Ironhelm]

As in, how to write music, or how to program synths, or how to get a good mixdown?

[ph00tbag]

When you start out with synth design, there's not really a set of rules for what they're "supposed" to sound like, no matter what part you do. Get yourself a decent subtractive synth to start off (usually, you can start with one of the basic ones built into your DAW, though I'd say it's good to expand into something like Synth1 later on, because it offers so many options for free), and screw around with the settings until you get something you like. The more you play around like this, the better you'll get to know what sounds good to you and what doesn't. This will serve two purposes. First off, you'll learn more about the synths you're using, because you'll be forced to learn every nut and bolt of the program. Second, you'll develop a style that works for you. Once you've gotten a basic understanding of how your software works, you can start using more specific tutorials to learn how to make certain sounds that you haven't figured out yet. This applies to bass, subbass, leads, rhythm, and everything in between.

As far as making melodies, I don't have a lot of good info for you. A working knowledge of music theory can helpis vital, though. For instance, it helps a lot to know what notes fall in a minor key and a major key, and what kinds of modes you can potentially be writing in. You can expand on that and learn about chord progressions and associated stuff, but it's best to start with the basics. Most of my theory I know through just playing music. I've never really studied it in depth, myself, but I'm sure some people here can point you to some really good reference material.

[Spirit]

Sub bass is just a pure sine wave that is routed to follow your main bassline
everything else is just trial and error, find a preset or make a patch, then experiment with melodies and such until you find something you like