First thing I'd say is don't start with investing. The foundation of solid finances is cash flow. Making more than you spend, reliably; knowing where your money goes; having a system that works for you to make sure you make more than you spend. Until you have that, your focus may as well be on getting there, because you can't fix much else about your finances until you fix this.
A number you want to know is your percentage of income saved, and a good goal for that is about 15%, with 10-12% going to retirement savings and the rest to shorter-term goals and emergency fund and so forth. (Of course the right percentage here depends on your goals and situation, but for most people this is a kind of minimum savings rate to be in good shape.)
Focus on your savings rate. This is your profitability, if you view yourself as a business. If it's crappy or negative, your finances will be a mess. Two ways to improve it are to spend less or to improve your earnings power. Doing both is even better.
The book Your Money or Your Life by Dominguez and Robin is good for showing how to obsessively focus on cash flow, even though you may not share their zeal for early retirement. A simpler exercise than what they recommend: take 3 months of your checking and credit card statements, go through each expenditure and put them in a spreadsheet column, SUM() that column. Then add up 3 months of after-tax paychecks. Divide both numbers by three and compare. (The 3 months is to average out your spending, which probably varies a lot by month.)
After positive cash flow and savings rate, the next thing I'd go through is insurance. Risk management for what you have. This can include checking you have all the important insurance coverages (homeowner's/renter's, auto, potentially umbrella, term life, disability, and of course health insurance, are some highlights); and also adjusting all your policies to be most cost-effective, which usually means raising the deductible if you have a good emergency fund. Often you can raise the deductible on policies you have, and use the savings to add more catastrophe coverage (such as term life if you didn't have it, or boosting the liability protection on your homeowner's, or whatever). Remember, cover catastrophes as cheaply and comprehensively as possible, but don't worry about reimbursement for non-catastrophic expenses.
I like this book, Smart and Simple Financial Strategies for Busy People by Jane Bryant Quinn, because it covers all the main personal finance topics, not just investing; and because it is smart and simple. All the main stuff to think about is in the one book and the advice is solid and uncomplicated.
Investing can truly be dead easy; most people would be fine with this advice:
- buy a single low-expense-ratio balanced fund or target-date retirement fund in your tax-advantaged retirement account (401k or IRA); keep putting money into it every month, at least 10% of income; leave it alone. "Leave it alone" means don't lower your savings rate, leave your money in the fund no matter what happens, and don't take out a loan from the 401k.
- find a good yield on a savings account or money-market fund from a reputable, convenient institution, and put your savings for pre-retirement goals (house, car, emergencies) in there.
- ... there is no 3. seriously, anything else you read is just micro-optimizing, or often undermining, the above plan, which is already fine for almost everyone even though it involves only two simple financial products (an all-in-one retirement fund and a cash account that earns some interest).
Honestly, I do micro-optimize and undermine my investing, and I'm guessing most people on this forum do. But it's not something I could defend objectively as a good use of time.
It probably is necessary to do some reading to feel financially literate and confident in an investment plan, but the reading isn't really because a good plan is complicated, it's more to understand all the complicated things that you don't need to do, since that's how you'll know not to do them. ;-) Especially when salespeople and publications and TV are telling you over and over and over that you need to know a bunch of crap and do a bunch of things.
People who have a profitable "business of me" are the ones who end up with a lot of money. Not people who spend a lot of time screwing with investments. (People who get rich investing invest professionally - as their "business of me" - they don't goof around with their 401k after work.) Financial security is all about your savings rate, i.e. your personal profitability. No shortcuts, other than lotteries and rich uncles.
