Symbols are composed of at least one symbol layer. Some symbols can also include symbol effects. Symbol effects dynamically alter the feature geometry before the symbol is applied to the feature.
The appearance and behavior of a symbol are dictated by the component symbol layers and symbol effects it contains. Even the order in which these components are placed in a symbol affects how the symbol appears.
To build complex symbols, you must manage the symbol layers and symbol effects within it. You can add, delete, and reorder symbol layers in a symbol from the Structure tab 
of the Format Symbol mode in
the Symbology pane. See the Use symbol effects topic to learn more about symbol effects, and how to add and remove them from a symbol. You cannot reorder symbol effects; you must add them in the order in which they should be applied. The symbol preview can help you as you build and modify symbols.
Tip:
The order in which the symbol layers and symbol effects appear in the Symbology pane is how they are layered when they are drawn. The symbol layers and symbol effects at the lowest position in the pane draw first, below all others. The layers and effects at the top of the pane draw last, above the others.
Add a symbol layer
To add a symbol layer to a symbol, complete the following steps:
- In the Format Symbol mode in
the Symbology pane, click the Properties tab and click the Structure tab .
- Under the Layers heading, click Add symbol layer.
- Choose a layer type: Marker layer, Stroke layer, or Fill layer.
- Click Apply to save the changes to the symbol.
Delete a symbol layer
To delete a symbol layer from a symbol, complete the following steps:
- In the Format Symbol mode in
the Symbology pane, click the Properties tab and click the Structure tab .
- Under the Layers heading, click the delete button
to remove the unwanted symbol layer. - Click Apply to save the changes to the symbol.
Reorder symbol layers
To rearrange the draw order of symbol layers in a symbol, complete the following steps:
- In the Format Symbol mode in
the Symbology pane, click the Properties tab and click the Structure tab .
- Under the Layers heading, click the reorder button
of a symbol layer and drag it to a new location in the stack. - Click Apply to save the changes to the symbol.
Duplicate symbol layers
Instead of adding a new symbol layer, you can duplicate an existing symbol layer in a symbol. This can save you time when building complex layers that have similar properties. Follow these steps to duplicate a symbol layer in the same symbol.
- In the Format Symbol mode in
the Symbology pane, click the Properties tab and click Duplicate layer
. - Click Apply to save the changes to the symbol.