This has been tested on windows 8.
Windows only recognizes the first partition of any removable device, this is where the problem lies while changing SD card or while making the amendments to your Ext partition. You apps will all be LOST if you format without care. Don't get hyper, this is quick and easy guide.
Things you will need.
1.Minitool Partition wizard home edition (probably the same which you used to create the partition)
2.Ext2 Volume manager.
3.Ext2IFS for windows.
USB mount is strictly not advisable, use a card reader. If you don't have any then use a mobile which is not an android, Nokia as for example.
1. Switch your mobile off, remove SD card. Insert it into card reader and then to USB port.
2.Windows will show you your FAT/FAT32 partition.
3.Backup your FAT/FAT32 partition. This is because you are gonna delete this partition.
4.After backing up open Minitool Partition wizard, delete your FAT/FAT32 partition. Be sure to delete this only, DO NOT DELETE EXT2/3/4. Apply those changes.
5.Go to Ext2 Volume manager and select the removable SD card. Double click on Linux partition. Then click on mount points and done.
6.Go to My computer and you will find your Ext2/3/4 partition as a removable drive. Backup this, be sure to copy all the files. Do not leave any file.
7.Now delete this partition from Minitool Partition wizard, your full card is empty now.
8.Create a new parition as primary and Ext2/3/4. Drag this to the far right. Be sure that all the unallocated space is before this Ext partition. Not even a single MB should be after this partition. Apply changes. Select the size of partition according to your convenience.
9.Copy all those EXT backup files to this Ext partition. Windows will show this partition now. If it does not, go to Ext2 Volume manager and do the steps you did before.
10.Now that you have created an Ext partition of your desirable size. Go to Minitool Partition wizard and create a primary FAT/FAT32 partition in the unallocated space. Apply changes.
11.Copy those backup files on this new partition of fat file system which you copied. Now the Ext partition will not be shown in windows.
12.You are done! Insert SD into your phone and power it on. The first boot will take a little longer than normal.
13.Go to link2sd and check the storage, you will be having all the apps + your partition size is increased/decreased now.
If you have any problems tell me.
To all those who want to create a pictorial guide, DO IT BUT INCLUDE A LINK TO MY ORIGINAL GUIDE.