You can increase troops' march speed by the following:

-Setting passive skills attributes to increase march speed for some military officers, such as Captain Aldo.
-Use March Boost or Advanced March Boost items which you can purchase from the store or acquire through events and purchasing packages.
-Conduct technology research in the institute that's related to troops' march speed.
-Activate and upgrade your VIP level.
-Upgrade Alliance technology.
-Upgrade Alliance level.
-Use some base skins such as World Cup and the Pyramid.
-Manufacture and upgrade pieces of equipment.