Open page

1. Login
2. Select "Modify profile"
3. Select the tab "LoTW"

Check for new QSL

4. Click "Account - Change"
5. Insert username (the username used to login into ARRL's Logbook of the World)
6. Insert password (the password used to login into ARRL's Logbook of the World)
7. Press "Ok"
8. Enable "Enable check" if you want to receive QSL confirmation from LoTW
9. Enable "Automatic update grid locator" if you want that HRDLOG.net updates QSO's grid locator according to data received from LoTW

Step 2 - Send new QSOs

Follow these steps if you want to send new QSO to LOTW
Important: Keep in mind that by enabling this function all new QSOs will be sent to LoTW using the inserted location.
Then enable this function only if you use the radio from a single location (home, hamshack, ...).
Don't enable this function if you use the radio from more than one location (field, activation, expedition, ...)

Get certificate

10. Launch the program TrustedQSL - TQSLCert
11. Select your certificate
12. Click "Certificate" - "Save"
13. Enter the PKCS#12 file name (for example your callsign) and press "Save"
14. Write a password (You must remember this password, it will be used in step 18) and press "Ok"
15. Enter your private password and press "Ok"

Setup certificate

16. Click "Certificate - Upload"
17. Press "Browse" and select the PKCS#12 file earlier saved
18. Insert the password (that used in step 14)
19. Press "Ok"

Setup location

20. Click "Station location - Change"
21. Insert "Station location name" (for example home)
22. Select your "ITU Zone" and "CQ Zone"
23. Insert "IOTA" if necessary
24. Press "Ok"

Final step

25. Check the box "Enable"

Source: http://www.hrdlog.net/docs/Lotw.aspx