Buy a blond wig with a widow's peak, if possible. The one detail most people fail to recognize about Marilyn Monroe is that her hairline had a pronounced widow's peak. Obtaining a wig with this feature is not easy, but it creates a strikingly accurate imitation.
Restyle your wig when necessary. Most wigs will come in a prefashioned state, but after multiple uses, the wig tends to lose its shape. Restyling the locks with a curling iron can restore its previous shape. This must be done carefully, particularly if the wig is not of the highest quality.
Solidify the style with a firming agent like gel or hairspray. Once the hair on the wig has been curled, it can be locked in place either with gel or hairspray. If gel is used, the amount applied must be extremely minimal as there were no traces of grease in Monroe's hair. Hairspray, while running the risk of making the hair look too crisp, is a safer bet for keeping the style intact.
Pay more money for the wig now so you won't have to pay for another one later. If the wig is going to be worn on a daily basis (i.e. impersonators or people who work in front of Mann's Chinese Theater), it is advisable to invest in a wig that is made from real hair.
Avoid getting discouraged. Remember, Monroe had a team of stylists to fashion that mound of hair on her head, so don't get frustrated if your wig doesn't look exactly like Norma Jean's after the first few attempts. Above is the most famous incarnation of Monroe's hair and even though it looks fairly simple, ample time and effort went into perfecting it.