- Bitcoin core. Once you install it, you'll get two executable, one for mainnet and the other for test net.
- Electrum. Find the shortcut (It should be in your desktop), right click it then choose "Properties" and add --testnet to Target.
- Mycelium (for android). You don't have to do anything.

If you end up choosing BitPay as suggested above, and you can't manage to create a wallet, that's because your country is banned, so you'll have to use a VPN to bypass that.