It's an unpleasant experience to witness racist vitriol or confrontation. It's even worse when you're on the receiving end of it. Those who have copped a racist spray or attack often say it makes them feel like a lesser being.

Not all racism takes such dramatic form. Sometimes it can be silent or subtle. But even relatively mundane acts of racism have an impact on those who experience them.

Everyday and casual acts of racism are the subject of our "Racism. It Stops with Me" campaign's new community service announcements. Since 2012, more than 400 organisations across the country have joined the campaign to support the work of anti-racism.

It is time, though, to sharpen our conversations about racism. Race relations across Western democracies have grown more strained. Xenophobia and intolerance are on the rise, fuelled by far-right political movements.

There's no question public debates about immigration and national identity can shape experiences of racism. Our leaders have an important role in setting the standard for racial harmony.

But we must never believe the work of countering prejudice must be left to our society's leaders. All of us have our part to play, in our everyday lives. Not least because racism happens in places such as our neighbourhoods and shops, our schools and workplaces.

Thinking about racism in everyday situations means we can focus on some practical actions.

This helps get us past one obstacle to countering prejudice and discrimination. Often people have been idle bystanders to racism, not because they accept or endorse it, but because they have been unsure what to do.

It's important we aren't just bystanders to discrimination – that we are prepared, whenever possible, to speak out or stand up. We must also support those on the receiving end.

Failing to do these things risks sending a dangerous message. It risks saying that those who deal out racism have a right to do so, without being called out. And that those who experience racism have to cop it sweet. Drawing the line on racial incidents can be straightforward when it involves an overt act of hatred or vilification. It's more difficult if it involves biased attitudes or misdirected banter. Even more challenging, perhaps, is racism that involves systems or institutions.

It's true that conversations about race must frequently deal with nuances. Much can depend on context. There isn't always a simple formula that can be applied in deciding whether something is racist or not. Still, some general principles can help. Here are four that can get us started.

It's not just about racial superiority. Racism refers to prejudice, discrimination or hatred directed at someone because of their race. It is something that creates disadvantages for some, and confers privileges on to others.

Expressions of racism don't always need to involve a belief in racial supremacy or even racial malice. Racial prejudice can emerge from more benign sources, such as ignorance or cultural anxiety. Grasping this gets us a long way to recognising when racism actually happens.

Words can do damage. Something doesn't need to physical harm in order to count as racist. It's not a case of "sticks and stones may break my bones but words will never hurt me".

We know that when racial violence does occur, it is often enabled by racist language. Consider the reminder of the Holocaust Memorial Museum in the US in response to the recent surge in white nationalism: "The Holocaust did not begin with killing; it began with words."

Let's not get too defensive. Race can be an uncomfortable topic; some of us prefer not to talk about it. That's one reason why some say we make too much fuss about racism in Australia when racism is much worse in many other countries.

A meaningful conversation about racism shouldn't be diverted in this way. Australia is by international standards a highly racially tolerant society. But that doesn't deny that those who experience racial discrimination experience a real harm to their dignity and equality.

Racism matters to all of us. Its presence should prompt our society to look in the mirror. Racism shouldn't just be an issue that matters only to minorities. And the work of combating racism mustn't be left to the victims of racism – for the same reason that we can't, for example, leave the task of combating sexism to women alone. Those fortunate not to experience racism must understand they have an important part to play. Social progress happens only when society is big enough to stand alongside those who are mistreated or experience injustice.

This is ultimately why our message on racism today brings it back to the personal. We say, "Racism. It Stops with Me", because racism diminishes all of us – and because all of us can help stop it.

Tim Soutphommasane is the Race Discrimination Commissioner.