Hi Regis, I totally understand about the cousins issue & getting them to test. I've got some 2nd cousins that I want so badly to test, and they just won't do it. Both of my parents are only children, so 2nd cousins are the closest I have.
As far as triangulation, that is a group of three or more people that share the same chromosome segment. So you can triangulate even when you are the only one that has tested. When people share a chromosome segment (greater than 7cM), it means they share a common ancestor. But you need 3+ to share that segment to 'confirm' the ancestor. So you identify people that all share the same segment, and then you look for an ancestor that you all have in common. When you do that, you can confirm the lineage up to that most recent common ancestor (aka MRCA) (usually an ancestral couple).
The advantage of having your aunt tested as well as you is that, if someone matches both her and you, you'll know it's up your dad's mom's side of your tree. So it'll narrow the focus down for you. If you could get someone that is related to your mom to test (a 1st cousin of hers or an aunt or uncle of hers), then if someone matched both them and you you'd know it was up your mother's side.
If you really want to use your autosomal DNA to help you confirm or build your family branches, then you'll need to use some software to help you with it. Fortunately there are some great products that are free! I use GenomeMate to track my matches & keep notes on contacts & what I've learned. It also lets you mark your MRCA once you've determined them (you load your gedcom into it). It's all done/stored on your computer, so nothing is online. You also should use DNAGedcom (again it's free) to triangulate matches. It gives you wonderful colored bars that help you easily identify the people that are sharing segments.
When you go to start looking for triangulated groups, start with the people that share the largest cMs with you. That means it's a more recent ancestor and typically will be easier to locate the common ancestor. If it's a very large segment, and no one else is matching the two of you, then feel free to go ahead and contact the person.
Mapping chromosomes isn't a quick, easy task. It takes a lot of time and research. I spend days making no progress whatsoever on a group. Or I'll get lots of clues but that elusive person just doesn't show up. I find it fun; it's certainly challenging; but if you are someone that wants instant gratification, it's not for you. Take time to learn about DNA and what it all means. Read everything you can get your hands on. And just take it slowly. Over time you'll get more comfortable with it. And when you break down a brick wall, you'll probably want to jump up and do a little dance! Just remember to keep it fun. If you get frustrated, leave it be for a bit. It'll only get easier in time as more people test and get to know about DNA.
Wishing you great success!