To fill out a check or to properly sign a checks you must know who to make the checkout to. The correct legal name is important. If your making a check out to the Federal Government you could use something like IRS or Internal Revenue Service. Do not make the check out to Taxes or Tax. There are hundreds of different tax institutions and banks want to know specifically who the check is for.
Spell out the amount you need to make the check out for. So $1,000.00 looks like "One Thousand Dollars" and 00/100 which means zero cents. I would put "One Thousand Dollars" and 50/100 or 50 cents if the amount was for $1,000.50 - Also remember to put in the correct decimal places and points for your check amount on the far right side in the amount box. If there is no cents you should still write .00 instead of just writing 1000 it should look like this: $1,000.00 (the dollar sign is not needed) usually it is already printed on the check for you.
Make sure that you put the correct date on the check. You can put a past date or a future date if you so desire. If however you put a future date and someone goes to cash it ahead of time they will be denied and the funds will not be made available until the date on the check.
Sign the check, not on the back but the lower right hand corner - sometimes there is an MP. and there usually is a line indicating where to sign.
Also remember to put some information in the MEMO section of the check. If you were writing a check for your rent or mortgage it would be important to put your apartment number or street number address.