Taking that steam a step further, a good old-fashioned steaming works wonders, especially if followed by the neti pot. If you are completely blocked, the neti pot won't work until you shake things loose with a good steaming.
I use a metal bowl or pan on the table with a bit of vinegar in it. Adding essential oils is great if you have them....I like lavender and either eucalyptus or any of the "Italian spices" like rosemary, oregano, basil, etc. I prefer lavender and rosemary, personally.
Boil a good-sized kettle or pan of water and bring it to the table and set it on a hot mat. Pour some in your bowl, add 2-3 drops of your eo's if using them, and use a dish towel around the pot to direct the steam to your face. Hold the towel around your nose and mouth and breath in...cautiously at first as steam can burn. You want to breath in those eo's ASAP if using, as they dissipate into the air almost immediately. Breathe through your mouth if your nose is completely blocked. Do this until you can taste the vinegar strongly and until things loosen up a bit.
Go blow your nose, and then repeat the steaming with more hot water and more eo's. Blow your nose again, then try the neti pot. This will loosen up the worst of the worst.