What do you want?
Ah, the age-old question. But if you're thinking about introducing a little bit of role play to your love life, it's important to think about what you want to get out of it.
Perhaps you want to try a little bit of bondage for the first time, but are too shy to introduce it, 'as yourself'. In which case, a spot of police-themed play is an easy and non-threatening choice - after all, you'll need the handcuffs as part of the uniform, right?
Do you want shake up your routine, but aren't necessarily comfortable with donning a full costume? Something as simple as popping on a wig or a new item of clothing, going to a bar with your lover and pretending to be strangers exchanging lingering glances across the room will bring back that excitement without taking you too far out of your comfort zone.
Consider as well the power dynamic that you're after. If you fancy the idea of your lover coming over all bossy and telling you what to do, role play situations that cast you as the submissive party are ideal (think secretary and boss, doctor/nurse and patient, or even master/mistress and slave). Fancy being in charge? Just flip the roles.
Whether you've got a clear scenario in your mind, or you're simply looking to try something a little different, it's always worth identifying your desires as it will help to inform how the role play unfolds, and take some of the pressure off both you and your partner.
Once you know what you want, it's time to discuss it. After all, if you hand them a skimpy firefighter outfit with no context, they may be a little reluctant to join in.
Explain exactly what you want to happen in your fantasy. If they know exactly what you're after, it becomes easier to improvise around the 'plot' rather than just winging it, which could lead to both of you feeling uncomfortable as well as not fulfilling your desires.
If you're worried that they may feel a little slighted by your fantasy, and suddenly believe that you're lusting after every police officer you see, try framing it in the context of a dream that places them in the role you want. "I had a dream where you were a police officer who handcuffed my hands behind my back and then had your way with me" is a little easier for some to swallow than, "I want to have sex with a cop."
It's also important at this stage to set your boundaries. Discuss with them what you are and aren't comfortable with them doing or saying. If you're involving any sort of bondage in your play, remember to set a safe word so that your partner knows exactly when you want them to stop.