Step 1

First you need to download DosDude Catalina patcher from http://dosdude1.com/catalina/ website by clicking Download Latest Version button.

Step 2

Double-click macOS Catalina Patcher icon to run it.

Step 3

Click Open button to run patcher. If macOS is blocking it you need to unlock it in System Preferences -> Security & Privacy -> General pane by clicking Allow button.

Step 4

Click Continue on welcome screen.

Step 5

Click Continue again on contributors screen.

Step 6

Click Download a Copy icon.

Step 7

Click Start Download to start downloading macOS Catalina installer image directly from Apple's servers.

Step 8

Downloading macOS installer image will take several minutes to complete depending on your Internet connection speed.

Step 9

Click Create a Bootable Installer icon to start creating a USB flash drive. You need at least 16 GB USB flash drive.

Step 10

Select your USB flash drive icon and click Start button.

Step 11

Click Yes button to erase all contents on your USB flash drive.

Step 12

Enter your user account password and click OK button to start creating a patched USB flash drive.

Step 13

Creating a patched USB flash drive will take several minutes to complete.

Step 14

Your patched USB flash drive is now ready to use. Click Quit button to close DosDude Catalina patcher.

Step 15

Boot your computer by pressing and holding Option key (on Mac keyboard) or ALT key (on Windows keyboard) and click arrow under macOS Base System to start macOS Catalina installer.

Make sure the USB flash drive is inserted into Mac Pro built-in USB hub (front or rear). Extra USB PCIe cards won't show a bootable flash drive.

Step 16

If you haven't created Catalina partition yet, you can use Disk Utility now. Make sure partition is formatted as APFS filesystem and using GUID Partition Map.

Step 17

Select Reinstall macOS and click Continue button to start installation.

After installation is finished you will be able to move all data from your old macOS partition.

If you use AMD Radeon RX 5500 XT/RX 5600 XT/RX 5700/RX 5700 XT graphics cards the system won't boot properly. You need to follow this guide: Installing MacVidCards patch for AMD Radeon RX 5500 XT/RX 5600 XT/RX 5700/RX 5700 XT/W5500/W5700 cards under macOS Catalina 10.15.5 or later

Step 18

If you are using a standard 802.11n Wi-Fi card you need to follow these extra steps.

If you replaced your card with 802.11ac card then you can skip these steps.

Again boot your computer by pressing and holding Option key (on Mac keyboard) or ALT key (on Windows keyboard) and click arrow under macOS Base System to start macOS Catalina installer.

Select macOS Post Install and click Continue button.

Step 19

Leave defaults patches selected and click Apply patches button.

Step 20

The system will be automatically rebooted.

Step 21

Upon reboot you might be prompted with Patch Updater window. Just click Install 1 Item button to finish the installation and again reboot the system.

The system will be now ready to use and Wi-Fi module will be working normally.