The shiny egg hatching process is different to the one you used in DPPt, as far as I know. I'm no RNG pro, but I can breed shinies in HGSS. I'll tell you what I did:
1. Open up time finder, click the Shiny Egg tab. Check 'HGSS Shiny Egg'
2. Enter all the details, including a seconds value and delay range you are confident you can hit regularly.
3. The date actually isn't important (unless you care about your shiny being hatched at some stupid date)
4. If no results come up when you press generate, try changing the date until something good comes up. Something 'good' is one with a frame as low as possible. This way you won't have to go through eggs and risk missing one (I won't go into details).
5. When you find a good seed, right-click it and select 'Generate More Times...'
6. On the screen that comes up, make sure it has the correct date and seconds, and check 'HGSS'. Find your seed on the list, and highlight/click on it. Click the generate button located on the middle right.
7. Now you should have a bunch of adjacent values as well as your desired seed.
8. Start the button-mashing sequence on your game. To see if you hit your target seed, immediately load up pokegear after pressing continue. Call Elm 9 times, note his replies, press 'Search Elm' in the middle, and enter what you got.
9. The RNG Reporter should now find the seed you hit. If nothing comes up, then you're either too far off your target or entered Elm's replies wrong.
10. Repeat step 8 until you hit your target seed.
11. When you succeed, you can now put your parents in the daycare and start collecting eggs.
12. There is no coinflip app in HGSS, so you have to go through each egg one by one (as the guide says). That is why you want an egg on the first frame, so the first egg you pick up will be shiny.
13. When you reach the frame of the shiny egg, save before collecting it if you want to SR for IV's.
I hope this helped.
P.S. I don't have any roamers roaming about on my game. So I've never had to enter their locations. Otherwise it should be the same process for you.
Hmm, do the delays have to match up exactly? Let's say in the first window, I choose a seed with a delay of 483. In the second window (Seeds to Time), do I have to get the exact same delay again (483) after I enter the Elm information?
EDIT***
Never mind, the seeds have to match up exactly. My mistake.