How to maximise one's chances of getting a good postdoc position? I am at the beginning of my PhD studies. Although that is a bit too early to plan one's carrier after thesis defence, one should still have some long-term goals in mind. Hence the question - what can one do during one's PhD (mainly as far as long-term activities are concerned) to maximise the chances of getting accepted for such a position?

Few things that come to mind:


High quality research published in high reputation journals (obviously).
Creating a contact network at conferences, research visits and through scientific collaborations. One might get to know one's potential postdoc supervisor or recommendation letters from established researchers.
Online visibility through blogging, social networking etc.
Good teaching experience. PhD students often have to teach but some might try to get on with the necessary minimum. Having a good record (e.g., from student evaluations) can be advantageous.
Experience with grant administration - helping one's supervisor with grant proposals, reports for grant committees etc.
Maybe some experience with paper reviews (towards the end of the PhD). Or is it still early for that?


Are there any other things I missed? I am looking specifically for the situation in theoretical physics and PhD without coursework but experiences of others might be relevant and interesting as well.
I am also in your current situation and look for the same. Here is something I have learnt so far which are important to get postdoc job in good quality institutes. Here is the list without order:


Publish in under-spot conferences and seminars 
Reference letter from pioneers of the domain (if you can liaise)
International collaboration, research, and publication
Face-to-face visit. If possible try to make an appointment with potential postdoc supervisors and visit them in person. It helps both of you to better evaluate and decide.
Search among friends of your friends for an open position. I use Microsoft Academic portal "http://academic.research.microsoft.com/" to search co-authors of my supervisor or academician friends of mine to see if there is any potential postdoc supervisor in their network. So you can give a try and if found, ask your supervisor or your academician friends to play a role and introduce you to potential boss. I think it should work well.
Upload your papers everywhere you can (take care of copyright issues) and try to increase their visibility and citation; the higher citation, the better chance. 
Make your professional account in Google Scholar and keep that up to date. 
Enroll in academic organizations like IEEE and get membership. It gives lots of benefits and is like a mark of attachment and care to the society.
Collaboration invitation. Try to prepare a paper and get in touch with potential postdoc supervisors to invite them collaborate. This can be a venue to exchange couple of emails and get to know each other more. You can later use this opportunity to request for position.
Try to get chance to visit potential labs as visiting scholar. some institutes welcome visiting PhD students under different schemas like student exchange or international collaboration.- Volunteer job in varied community; not necessarily academic environment. Try to show your passion to work independently in every workplace regardless of the details.
Online Connectivity. Active participation in online networks like Linkedin, Researchgate, stackexchange(here), and so on.
Patent is also important since institutes are increasing concern about patents and desire their postdocs to produce patent beside publication. It also enhance your industrial career too. 
Keep sending application for advertised positions and don't get disappointed.
Keep sending email and follow up to potential postdoc supervisors with potential postdoc projects (it depends on your field) even if they have no current position. Your messages may impress them and motivate them to hire you to work on a project you define. If yes they can apply for funds (I know one of my friends in CS got offer in this way).


I hope these points help you better hunt a good postdoc in good research group.

EDIT: Patent is modified to address some concerns on wording.
EDIT2: Some change in the order to better highlight their importance.