The align options in the settings panel will help align or distribute selected objects along the axis you specify. The Align options are visible when an object is selected.
To select multiple items hold Cmd/Ctrl + Click and then click the button for the type of alignment or distribution you want.
Align Left Edges
Align Horizontal Centers
Align Right Edges
Align Top Edges
Align Vertical Centres
Align Bottom Edges
Distribute Horizontally
Distribute Vertically