Should you include yourself as a federal tax allowance?

If you are filling out Form W-4, yes, in most cases you count yourself for at least one allowance. (See the IRS instructions--link below--they're pretty straightforward).

If you are filling out a tax return, then "allowance" is probably not the right Word and perhaps you should ask the question differently. If you are not referring to US Income Tax, then you should be more specific.