We've talked about things you can do to increase the total of your Schedule A deductions for 1984 if you itemize on your federal tax return. If you don't expect to be able to itemize, then follow a reverse strategy: Delay as many deductions as possible until January on the chance that you might itemize next year.

If you fall just short of reaching the zero bracket amount each year, a strategy of "alternating" might get you a lower tax bill. The trick is to do your tax planning in two-year chunks.

If preliminary estimates show you can't itemize for 1984, you want to delay payments that qualify as Schedule A deductions until next year, and take the zero bracket amount for 1984.

As you approach the end of 1985, you should accelerate as many qualifying expenses into 1985 from 1986, using the ideas I mentioned last week. By bunching as many 1984 and 1986 deductions as possible into 1985, you may be able to use Schedule A on your 1985 return.

This strategy gives you a lower tax in 1985 by the use of Schedule A itemized deductions rather than the zero bracket amount. But it does not increase your 1984 or 1986 tax, because you always get the zero bracket amount no matter what.

Using that strategy, let's talk about how to get maximum tax mileage out of political contributions.

The tax credit for such contributions is available to all taxpayers whether you itemize or not. The credit is equal to 50 percent of your total qualifying contributions, with an annual ceiling of $100 on a joint return, $50 on a single return.

If you're single and planning a one-time $100 contribution to a political party or specific candidate, you'll get the maximum $50 tax credit no matter when you make the contribution. (A married couple filing a joint return can just double the numbers in this example.)

But what if you're planning a larger contribution -- say, $200? If you contribute the entire $200 this month, you'll be limited to a $50 credit on your 1984 return. Similarly, if you give the entire amount next month the credit (on your 1985 return) will be $50.

On the other hand, contribute $100 this month and the other $100 in January. Now you can reduce your 1984 tax by $50 -- half of the 1984 contribution -- and claim another $50 on your 1985 return. Your chosen party or candidate gets the same $200, but you end up with a total tax saving of $100 instead of just $50.

If you intend to deposit money into an IRA, you have until April 15, 1985, to make the deposit and still claim the adjustment on your 1984 tax return. But there is a change from previous years: If you request an extension for filing your tax return, the final date for IRA payments is not extended with it -- it stays April 15.

Be sure to identify the year to which your payment refers when making a deposit after Jan. 1. IRA sponsors are now required to report to the IRS not only all IRA deposits but also the tax year each deposit represents.

Keogh accounts don't enjoy the same timing flexibility as IRAs. Although you may make deposits on your 1984 Keogh as late as April 15, 1985, the account must have been established by Dec. 31 of this year. So if you don't have the cash for the entire 1984 Keogh contribution, be sure you open the account with at least a token payment by year-end.

The IRS recently ruled that custodial fees paid on an IRA or Keogh account may be deducted as an investment expense under miscellaneous deductions on Schedule A -- but only if paid separately.

If your custodian has been simply charging your account periodically for the custodial fee, ask to be billed separately. If the fee is charged to your account, you can't claim it on your tax return -- it simply reduces the eventual payoff.

But if you pay it separately, you get two breaks. If you itemize, you get to include the fee as an itemized deduction. And -- whether you itemize or not -- you can contribute the full ceiling amount ($2,000 for an IRA) in addition to the separately paid custodial fee.