The TSR Pokémon Society III

Before or after beating magma/aqua?

I'd say watch the video, I have a feeling you missed something out.

both - before & after. I've looked at the video and I've done everything.

Have you tried going to route 110 and not route 109 after beating Archie/main aqua guy at the museum?

Here's a written walkthrough:

http://www.marriland.com/omega-ruby-alpha-sapphire/walkthrough/dynamo-badge/5267-slateport-city

I have also done most of Route 110 yes and still no luck getting into the contest. The only thing I can see is that I don't know how to make pokeblocks

Ahhhh, you may need the poke block case

ignore, I think ive worked out how to make it. Thank you so much for the help

You can get one?

ignore, I think ive worked out how to make it. Thank you so much for the help

You can get it now?

I spoke too soon. Made a pokeblock and still no contest entry :/

Speak to both receptionists.

it worked thanks Thank you again

Please tell me you didn't talk to the wrong one over and over again?
No worries though! Once the contest is over, a breeder will come up to you and she'll give you a cosplay pikachu. You can change its appearance anytime by going into the back room

Got two Shiny Articuno yesterday.

I hadn't found a shiny Pokemon in any game for about 10 years since the original Ruby, then last month I found three in a week (including two in the space of 5 minutes)!