Set yourself attainable objectives to motivate yourself to do sport
When you get back into sport after a long break, needless to say that the most difficult thing is to stay motivated in the long-term. Most people tend to aim too high, too quickly. And the more disappointed you will be when you do not attain the objectives set.
There is clearly no point in running a marathon after two weeks of running training, or bench pressing 100 kg 5 days after joining your local gym. The key is to make gradual progress!
Start by setting yourself a programme that is suited to your current level of ability so that you do not get demotivated. By taking things step by step, you will stay inspired and calmly work towards your target.