I am having trouble increasing the quality of my sound in the videos I film. I am working on a very low budget because I am a student, I use mostly an iphone and a lavallier. This doesn’t seem to be enough. I know that pros use special gear to separately film (or purchase) background sounds such as steps, wind etc. I would want to try and record some of it myself with my gear. Also, when people speak in my videos, their voice is not so clear if I film outside and there is traffic.

Any advice?

You could either edit the sound afterwards, which can be difficult especially if you have little to no experience in sound editing or you can try using foliage from the internet. You can find a few free samples that you can use and there are also premium bundles that you can purchase for a small fee. 

Hallo Julia,

It is difficult to do so without special equipment. You could try to talk into the microphone of your headset. This is a low-budget trick that sometimes works.