Tip 1: Reduce your drag
Don't wear baggy swimwear. Tighter swimwear is more streamlined. You can also reduce drag by wearing a swimming hat. You can also reduce drag by improving your technique and body position - I wrote another blog post about this here.
Tip 2: Breathe less when sprinting
Every time you breath you are creating resistance. When Olympic swimmers sprint the 50m freestyle they often only breath once in the whole race. This is also about using anaerobic systems rather than aerobic systems.
Tip 3: Don't crossover your arms
Crossing over means your arm pull crosses over the center of your body. This means you are kind of wiggling side to side through the water. It is a very common mistake that beginners can make when swimming front crawl.
Tip 4: Shallow and fast leg kick
Your legs are like your propeller, they provide balance and propulsion when swimming front-crawl. Your legs should be in the water but not in too deep - the leg kick should be shallow, powerful and fast.
Tip 5: Lengthen your stroke
Having a short front crawl stroke means you are grabbing less water. You want to be grabbing as much water as possible. The more water you can push behind you the faster you will move through it.