One of two ways
- You have iTunes and Microsoft Outlook: You can go into iTunes, select the iPhone, then info tab, then select MS Outlook as your default service. Be sure to do it with all features there.
- You have a compatible Microsoft Exchange or iCloud service: Simply add the service to MS Outlook. You can find setup instructions on any MS Exchange service you have including iCloud or visit iCloud.com if you are syncing OTA and don't have an MS Outlook program.
You can sync your iPhone contacts with iCloud. Then log in to your iCloud account from your laptop, go to Contacts and hit the "Export" button. There are a number of additinoal ways - ie.e sync your iPhone contacts to an email account and do the same as above but from your email account. Here's a couple or more methods of how to achieve this: How to Backup iPhone Contacts