Instructions
Examine the date on the dollar coins you with to use. If the date is before 1964, it has significant silver or gold content and is worth much more than its face value. These coins should not be used as one-dollar coins. Instead, these old dollar coins should be collected or sold to a collector or bullion buyer. Silver dollars are currently worth no less than $15 while gold dollars are worth no less than $90.
Use a dollar coin as you would any other type of currency when buying something from a clerk.
Read any instructions on a vending machine or other automated machine before using dollar coins in them. Some do not accept dollar coins and, even if they do, they probably only accept the current issue coins, and may not take the differently sized Eisenhower dollars or the differently shaped Susan B. Anthony dollars.
Wrap dollar coins in coin wrappers when taking them to the bank. The bank should be able to supply these to you if you cannot find them elsewhere.