tl;dr to the above: The most common frauds are so-called high-yield investment programs.
Avoid any and all 'investments' that promise a 'high-yield', no matter how glib the rationale. Another tip-off is a promised guarantee of value:
if you see a promise that 'guarantees' $X for an alt, run away.----------
Since you're interested in mining,
watch out for new-miner frauds. To protect yourself, only buy mining ASICs/equipment that already exist and can be shipped out as soon as you place your order. Leave the "pre-order" arms race to folks who've been around the block and/or are rich enough to absorb any losses from scammers.
If you want to get rich quick and are currently "down on your luck,"
tread carefully. I had to learn this one the hard way: the toxic combo of having little money and seeing other folks getting rich will leave you psychologically vulnerable to a lot of scams. If you feel obliged to play "catch-up," try doing nothing that costs any money until you work through that vulnerability. It'll help a lot if you're patient with yourself. You actually have a lot of time: a recent Coindesk article predicted that blockchain fintech
won't be mainstreamed for a decade. That timeframe gives you a lot of leeway for taking it slow.
You'll save yourself a lot of time and effort if you
stick to one alt. Another one I had to learn the hard way. There's a heckuva lot going on here, and trying to keep up with it all can easily consume most of your day - sometimes all of your day. It's seductively easy to become a Bitcointalk forum junkie. In addition to avoiding forum-junkiehood, sticking to one alt is good time management. It'll give you the time to acquire the technical skills to figure out what goes on "under the hood." Having those skills will win you a lot of respect around here.
I managed to calm myself down a lot by seeing altcoins as essentially a
fun and exciting hobby with potential to change the world. This attitude enabled me to flush the "get-rich-quick-itis" out of my system.