The stock market is full of uncertainty, but there’s one thing you can count on: You can always find a reason to kick yourself.

Right now it may be that you sat on the sidelines and missed the spring’s wonderful gains. Not long ago you might have kicked yourself for staying fully invested while the market plunged.

With the recent turnaround, many experts say investors are looking for ways to pile back in to stocks.

Hopefully, they’ve learned their lesson. Even the pros cannot reliably predict the markets peaks and valleys. Amateurs who try to do so tend to get out too late, waiting until a downturn has already done its damage. Then they wait for proof a rebound is real before getting back in, missing the best gains.

In other words, they turn good investing strategy on its head, selling low and buying high.

For most ordinary investors, it’s better to stay in the market all the time, assuming you’re not buying stocks with cash you’ll need in the next five to 10 years.

Figures on long-term market performance, such as a roughly 10 percent annual return stocks enjoyed in the 20th Century, assume the investor’s money stayed in the market the whole time, and that all interest earnings and dividends were reinvested in the same holdings.

If you’re sitting on a wad of cash you want to put into stocks, what’s the best way to do it now?
Instead of shoveling it all in on one day, most investment advisors would advise spreading the purchase out over a year or so, putting in equal sums every month.

If the market dips, your monthly sum will buy more shares. If it jumps, the sum will buy fewer. The process minimizes the average cost per share.

Although sitting on the sidelines might have been a mistake, having a pile of investable cash presents some opportunities.

First, you can return to your target asset allocation by, for example, buying the types of investments that have been hammered the hardest. If stocks now represent 50 percent of your portfolio rather than the 60 percent you intend, the lion’s share of new investments should be in stocks rather than bonds.

Next, you can select investments that will be kinder to you at tax time. Index-style mutual funds, for example, tend to produce smaller annual tax bills than actively managed funds. That’s because indexers have smaller year-end distributions due to their buy-and-hold investment strategies.

You might also favor funds that charge lower fees, since even small-sounding fees of 1 or 2 percent a year can chew deeply into returns over the long term. Again, indexers are good for this. The market-data firm Morningstar Inc. (Stock Quote: MORN) has fund screening tools on its web site.

Since pacing your new purchases over 12 months means you’ll continue to hold cash, try to get the highest interest earnings you can. Money that won’t be invested for six, nine or 12 months can be locked up in CDs. According to the BankingMyWay.com survey, 12-month CD yields average about 1.24 percent, more than double the 0.47 percent yield on money market accounts.

Using the shopping tool you might do considerably better.
It also might pay to look at flex CDs that allow early access to your money. If the stock market takes another dive, this would give you fast access to cash for a buying opportunity.

Finally, consider ordinary savings accounts, as some deposit-hungry banks are offering good deals. Discover Bank (Stock Quote: DFS) pays nearly 2 percent on deposits of $25,000 or more.

— For more ways to save, spend, invest and borrow, visit MainStreet.com.