Dear Karma,
Beginners to mindfulness should start with a simple mindfulness exercise which introduces them to the experiental concept of mindfulness. I usually always start with the raisin exercise (originally from Mindfulness-based stress reduction). Then for homework I would suggest the client eats one meal a day, or even drink a cup of tea with full awareness and mindfulness until our next session. Unless the client has had previous mindfulness/yoga/meditation experience I don't get them to sit for any period of time until about the third session.
Recently returning from a quiet yoga retreat overseas to city life I find most have people very busy minds. There is distraction everywhere, which only feeds stress. A good example is the internet and smart phones, which quickly take people out of the present moment. People are constantly doing, they are not being in the moment. Mindfulness is the exact opposite of manner in which society seems to be going. Mindfulness asks you to go slower. Mindfulness wants you to look inside.
My suggestion is to not judge yourself for finding it hard to switch off. Just be in the present. When you are using technology say to yourself I am on my phone right now, or I am choosing to distract myself by watching television at the moment. Be aware of what you are doing and sit with your emotions.