Getting started in sampling
You need to know Dance Music inside out. The genre of Dance Music is divided into many different sub-genres. Make a slight mistake on any of the basic sonic components and you will be out-of-genre, which is possibly the biggest mistake a budding Dance Music producer can make. Since Dance Music evolves so rapidly there are no rules (except for the ones that are already out of date). You have to watch and listen. Go to a club that plays your favourite kind of Dance Music, watch for the tracks that get people on the dancefloor. They are the tracks to analyse and imitate.
You need to know your record collection - where the best samples are likely to be found. The more you use samples, the more you begin to recognise potential in records where others might give up and say, "What's to sample on that?". Sometimes you will take a sample and you just can't make it work. Don't worry, you took a chance and failed. Next time you'll take a chance and succeed. Some people are too scared to take chances.
You need to respect the laws of copyright. You might take a chance on using an uncleared sample on a record that will only ever sell a couple of thousand copies. You might get away with it, or you might not. It's up to you to consider what might happen if you get caught. One day, you'll want people who sample your records to pay you for the privilege. Why not start operating like a pro right now and get your samples cleared?
The equipment you need...
Dance music is created using samplers and computer sequencers. DJs might like you to think that they do it by clever turntable tricks. They might impress a live audience but in the studio an altogether better degree of precision is required. When your loops and rhythmic elements are in place, courtesy of your sampler and sequencer, you can add turntable effects either live or, more controllably, by another layer of samples.
If you can manage without vocals, or just the occasional vocal sample, then your basic kit will be a sampler and computer sequencer, and of course a pair of decks and a mixer to get your source material.