know the meanings of the words....
dictionary.com has this meaning for "effect"
ef·fect[ih-fekt] Show IPA
1.something that is produced by an agency or cause; result; consequence: Exposure to the sun had the effect of toughening his skin.
2.power to produce results; efficacy; force; validity; influence: His protest had no effect.
3.the state of being effective or operative; operation or execution; accomplishment or fulfillment: to bring a plan into effect.
4.a mental or emotional impression produced, as by a painting or a speech.
5.meaning or sense; purpose or intention: She disapproved of the proposal and wrote to that effect.
verb (used with object)
10.to produce as an effect; bring about; accomplish; make happen: The new machines finally effected the transition to computerized accounting last spring.
and this is the dictionary.com meaning for the word "affect"
1 [v. uh-fekt; n. af-ekt] Show IPA verb (used with object)
1.to act on; produce an effect or change in: Cold weather affected the crops.
2.to impress the mind or move the feelings of: The music affected him deeply.
3.(of pain, disease, etc.) to attack or lay hold of.
4.Psychology . feeling or emotion.
5.Psychiatry . an expressed or observed emotional response: Restricted, flat, or blunted affect may be a symptom of mental illness, especially schizophrenia.
6.Obsolete . affection; passion; sensation; inclination; inward disposition or feeling.
and once you know the meaning of the words.... use synonyms of the words in the sentence you are using them in