Step One: 
Assert without evidence a rule about the physical universe. Present this rule as universal and unbreakable. Examples include, but are not limited to "everything in the universe requires a cause" or "everything that is complex requires a designer." 

Step Two: 
Assert without evidence a being or principle that is exempt from the universal, unbreakable law you posited in step one. Examples include "therefore, because everything has a cause, something must have caused it that had no cause" or "because everything complex requires a designer, things that aren't complex require a designer, too!"

Step Three: 
When the atheist points out the obvious flaw in your reasoning (by breaking your own unbreakable law your argument refutes itself), assume they just don't understand the depth and complexity of your argument. Find a new audience--church groups are a good place to start--to present your arguments to. Remember, you don't need facts, logic, or even to address the objections to your argument if you simply repeat it enough times to audiences who have already accepted your conclusion (and have a deep psychological need for it to be true) before you even began speaking.