Patches applied differently for db2020 phone and non db2020 phones, for db2020 phones you have to bypass its security and for non db2020 phones patches applied directly
db2020 phones are :-

K550, K610, K618, K770, K790, K800, K810
S500
V630
W580, W610, W660, W710, W830, W830, W850, W880, W888
Z610, Z710

For non db2020 phone, skip the step for bypass db2020 security and just apply patch

For applying patch you need
SETool 2 Lite V1.11
and
USB Flash Driver…..

Here is the Video Tutorial

You must do this one time! After that you will skip all this process!!!
1. unzip it and run setool2lt.exe
2. Select your phone type and click on Read GDFS; tum off your phone and connect it by pressing “C” button.
3. it will backup your phone’s GDFS.
4. Now try to find out qamaker.exe on qamaker folder;
5. Copy your main firmware file (.mbn) to the qamaker folder;
6. Drag the MAIN file (.mbn) that you have in your phone on to qamaker.exe
From the qamaker folder that comes whith SETool2 Lite 1.11; this will create a vkp file;
(or here are some “quick_access” patches for Download)
7. The vkp file created in step 6
(like “quick_access_W610_R8BA024.vkp”) put it in to MISC FILES;
8. Select phone type and Click bypass db2020 security next to phone type;
9. Add the main FW (.mbn) file (like you would like to flash it);
10. Press FLASH button; connect your phone by pressing “C” button.
11. Follow the instructions given by setool2 lite.
Be carrefull! At one moment you will belive that nothing happens and the status windows is not changing! Not remove the CABLE! untill it tells to do.
Wait until “ELAPSED x SECONDS” appears in status window.
This process will take some time, about 10-15 minutes or more…. Remove battery and reinsert it………

After this process, follow this steps for every patch with the condition to check “Use “quick access” patch” and uncheck “bypass DB2020 security” on next to the phone type:

Here is the video tutorial

1. Select phone type
2. select “use “quick access” patch“
3. put your custom patch on MISC files; (here are some patch for W610i R8BA024, Download….)
4. Click on Write SCRIPT
5. Connect your phone, SETool 2 Lite will apply patch….
6. When it shows you to unplug the phone, than unplug your phone and turn power on.
Enjoy With Your Custom Patches……..
Here you can find patches for all DB2020 phones…..
Thanks to Akshay…. for the photos…… Thanks to se-tuning………
also thnx to akapu