Packing-pa-looza

I leave THIS WEEK Thursday for California! SOOOOO excited (as if you couldn't tell) anyways. I have begun the packing-pa-looza. This is sort of a complicated trip to pack for due to several factors:

• I am running Tinkerbell Half Marathon
• I am optimistic about the weather being super warm but concerned that I am not packing warm enough clothes, so I then in turn want to throw in a whole bunch of warm clothes
• I am attending a conference for work after running Tinkerbell - this doesn't require work clothes but it does require more than sweats
• It is ten days - I don't want to over-pack but under-packing sucks once you get there

It is always a challenge to pack, I always try to pack as simplistically as possible but when there is so much going on it is a challenge for sure. I am a believer of the roll your clothes method and put things in your shoes. 

I also have my backpack to pack as well. For me I will be carrying on my running shoes (everything else can technically be replaced if they have to but it is impossible to get a well worn pair of running shoes), my ipad, my phone, some yarn (I need something to do on the plane), my running watch, and a snack or two (I hate buying expensive airport food). I probably will throw some other stuff in my backpack, I just haven't gotten to that stage yet.

Anyone have any tips for packing light?

Anyone else have a love/hate relationship with packing?

What are your necessities in your carry on bag?