Bicycle

Invest in a bike. Getting places is so much easier (weave in and around traffic, disobey road rules). It saves you money as you don't have to spend it on fuel and parking tickets. It will get you fitter, help your general well being and will help with losing weight. It can also allow you to drink alcohol at places as you have a mode of transport home. Trust me, drunk ride homes are a breeze.

Any bike will do - A road bike will probably help the most. You can normally pick these up quite cheap second hand. Give them a quick wash and maybe new rims, tyres and tubes. Then it's good to go.

Pro-tip: A 10k ride will take roughly half an hour!

Sneaky!

Have you ever lost a phone charger? Next time you do, don't buy a new one. Phone chargers are the number one left behind item at Hotels. They usually have a big bin filled with every phone charger imaginable! Go to your nearest Hotel and say you lost one. Chances are you have, just at a different hotel!

Most stores stack their products from the back as they want to get rid of items that will expire first. Therefore always take from the back to ensure the freshest product. Works with basically everything, drinks and ice cream/yogurt are the ones you should look out for.  

Generic but people still don't do it!

If you're feeling tired or sluggish go for a walk or a jog. Getting blood flowing through your vessels is a great way to wake you up and help with your overall wellbeing. Lifting weights or doing simple body weight exercises (chin ups, push up etc)  will also help, however, not as much as cardio!

Protip:
-It will help you lose weight if you previously did no exercise, whilst maintaining  the same calorie intake.
-Mixing in healthy food such as an apple or banana will also help your general wellbeing!

Guides on how to run properly to avoid injury can be found here.
A great website to learn how to lift wights can be found here.

Save money!

Instead of buying one packet of chips from a vending machine or store, buy bulk from a super market or online.
This saves a lot of money!

When going to a venue(sporting game etc.) bring food and drinks as usually the price will be ridiculously high.

Change your own cars oil. This doesn't take long and there are a variety of guides and videos online on how to do it.

When purchasing an item, think whether or not it will still be useful in 3 years. This stop you from buying stuff like the shake weight etc.

When needing battery's it is always cheaper to buy a bigger battery and hack them like this!