First time investor here. Where should I start?

First time investor here. Where should I start? I am looking for feedback as to what could help save me time, trouble. Where did you guys start and what are some pitfalls you've learned to avoid? Resources, apps and pages you recommend? I have some cash I would like to invest and I understand many have asked this question before but wanted to see where I could begin and then maybe help others with what I have learned.