You know that motivation is not something we naturally have, it's something that you have to cultivate within yourself. Every motivated person you meet can also go through times of feeling unmotivated and stuck. It happens to ALL of us.
The trick is to not let this period of unmotivatedness (I know.. I know it's not a word but it should be!) get you down. Don't let it take over your life. There is a natural ebb and flow to motivation. You will go through periods where you are on top of the world and nothing can stop you which will be followed by an ebb which will be a period of lack of motivation and you just could not be ass'd.
Just let the ebb and flow happen without it becoming stuck in the down period. Don't beat yourself up about it either because this will make it worse.
Here is some tips to get yourself motivated and help you stay there consistently;
If you have a big goal you wish to achieve break it down into small ones and just focus on that ONE little goal. Once you achieve that little goal then set the next one. Too many times people focus on the big one and it can seem unobtainable and too far out of reach. This would be enough to turn anyone off even trying.
If you set little ones you are more than likely to succeed. The more you succeed the better you feel and the more motivated you will become.
Another problem I see is people trying to achieve too many goals at one time. What usually happens is your focus is every where which makes it impossible to achieve one goal well. You need to laser focus on just ONE goal until you achieve that and then move onto the next one.
Find inspiration and surround yourself with it. Whether that be pictures of inspiring people, hanging your "skinny jeans" up so you see it everyday or just listening to other people's success stories.
Tell every Tom, Dick and Harry about your goal. If you have any integrity this will motivate you to go for it. Otherwise you have to explain to everyone why you decided to quit.
Get excited about the goal. Think about what it would feel like to achieve it. How happy would it make you? Really visualize yourself achieving that goal. Then use that energy to push yourself forward into some form of action straight away. There is no better time then RIGHT NOW!
Celebrate every dam mile stone whether it be big or small. Now I'm so guilty of this one. Once I achieve something it's onto the next thing without ever stopping for a moment and really thinking about how far I've come.
Success is a great motivator though. The more results you see the more motivated you will get so really looking at where you started and comparing it to where you are currently can really help. Even if it may be as "small" as Last week you didn't exercise at all, but this week you exercised twice. This will fuel the fire.