Communication is key. Let your girl know you need to have a talk with her. Ask for enough time to discuss a few things with her so neither of you is rushed into having the conversation. You don't want to be in the middle of broaching the topic to her and she has to go to work or is distracted by someone popping in at your house.

Spell out exactly what the issue is. Women tend to need details and analogies, maybe even several of them so they can paint a picture of the problem in order for it to register. Don't talk all around the edges of the subject, clouding her mind with useless fluff. Be prepared to let her know how you feel, what you've decided and your reason why.

Let her know what it isn't. As she is likely to wonder what hidden intentions you might have, reassure her of your reason for needing space. This is the time when you need to be honest. If you feel like you want to meet other people or that being with her is distracting you from something you're working on, say so. Don't cower from the real issue in hope of saving her feelings. Avoiding the truth now will cost you a lot more heartache and drama in the long run.

Take your space. Once you've been granted the space, make use of it. Don't confuse the situation by asking for space but then performing as if everything is business as usual, by communicating daily and spending the same amount of time together. Use the space for whatever reason it was that you requested it, and let her adjust to the new schedule.

Give yourself a little extra time. If you only asked for a few days or weeks and find ut that that's not enough, give yourself a little bit more time and allow her to spread her wings and adjust appropriately. Remember that she has feelings, too; no matter if she took the request hard or willingly, give her the chance to enjoy the space and find out what it feels like without you.