1. Case-USAGE and spaces

Start the value-name with a lowercase letter. After the first word every word should start with an Uppercase letter.

wrong space value

wrong case value

wrong uppercase usage

just write:

int numberOfPeople = 10;

2. length

Write a value-name which shows it’s meaning in as less letters as possible.

wrong value name

just write:

int x = 1;

3. never start with a number

don't start with a number variable

just write:

int event1 = 10;
int event2 = 20;
int event3 = 30;