There's a lot to this and I suggest you read the threads which are already created for this purpose. This site already has advice for beginners and mining, with external links where necessary. Also baikalminer has links to tutorials for setting their miners up. Once you've gone through this...
Baikal is the way to go on DASH mining at the moment, but their own website is usually out of stock, and not very good at updates. Having said that, Baikal are very reliable once you place an order. I absolutely trust them. They're based in China and you need to get comfortable with ordering...
You can get them direct from Baikal now, but I don't think the supply will last long....
I guess I'll have to pay another visit to AliExpress for the power supply!
Just to mention, 0.3 Dash/week is slightly less than I am averaging with my 150MH/s hashrate!
With your Giant, you should be mining more than that.
I've just bought a Baikal "Cube" so I'm looking forward to see what that can do!
I guess you've figured out out by now, but if not, here goes:
I'm a noob, but I have a baikal mini-miner and at the moment I only use p2pool. I've tried others, but always came back to p2pool. I can't post a link, but put www. before: p2poolmining.us/p2poolnodes/ and check out which nodes are...