Go south from Mt Chimney, and just pass through the forest below. Take whatever items you see, and be sure to fight everyone. Then go west towards Lavaridge Town. Talk to one of the old ladies, you will recieve an egg. Inside it will have Wynaut, the pre-evolution to Wobbuffet. It will have Splash, Charm, and Encore as its attacks when it hatches. This Town is quite small, so you should easily spot the Gym. It is the fire gym. Each room will have a few 'pits'. Each pit will send you to another location. However, each room as 1 trainer hidden inside a pit. I have been getting some complaints about this gym, so I made a map for it, and a small walkthrough for that area, which is below. The Gym Leader, Flannery, has 3 Pokemon, Slugma, Slugma and a new Pokemon, Torcoal. This gym was easier than the others, but is still hard if they manage to pull of a Sunny Day. Both Slugma are level 26, and give 433 Exp. Torcoal is level 28, and is a pure Fire type, despite the fact it looks like it may be Poison or Rock. It will give 966 Exp when beaten. When you win, you will recieve the bagde, which allows you to control Pokemon upto level 50. In addition, you will get 2800 Yen and TM50. Also, you can now use Strength outside of battle! Once you leave the building, your Rival will come, and give you an item that allows you to walk in the Sandstorm!
Ok here is how this gym works. Each pit will drop you down a level or rise you up one. So when you start just go to A, and you will come out the other A. There are a few times that you will fall down and you wont be able to come back, like at E and G, but thats ok. Just continue on forward and you'll be fine. The trainers you see challange you if you get in thier line of sight.
You can continue to explore around, but now its time for the next Gym! Go to the first Gym that we saw, back in Petalburg City. Its a Normal type gym. The Gym is not really a puzzle. Each time you beat a Gym Trainer, all the doors ahead of you will open. Each Trainer has only 1 Normal type Pokemon. I recommend fighting them all, as the Gym Leader can be tough. The Gym Leader, Norman, is your dad! He has 3 Pokemon, which are all new. He has a Slaking, A Vigroth, and another Slaking. The first Slaking is level 28, and can be quite annoying, and gives 1360 Exp. However he is not too hard to beat. The second Pokemon, Vigroth, is level 31, and has a powerful attack which can cause alot of damage. However if you have a steel or ghost type, you shouldn't have a hard time. He gives 810 Exp. The third Pokemon is the second Slaking that he has. He gives 1395 Exp, and is also quite annoying. When you beat Norman, you will get 3100 Yen and TM42. His badge will also allow you to use Surf. Don't have surf? Well one of the houses near the west of the City has a guy that will give out HM03, Surf. But now, head back to Mauville City, the Electric Gym Leader, Wattson, will be walking around, so talk to him for an item.
Now go south a bit, to around the north entrance to the Bike Path. Surf on the water and go east. You will find a cave. It is filled with Magnimites and Voltorbs. There are also buttons on the ground. If you step on one, some doors will open, and others will close. This is place is not very large. At the end, you will find a button that turns off the generator, and a Thunder Stone. Now make your way out of the cave, and go back to the city above you. Go east, and with Surf, you should be able to make it across! Its a very long way to the next City. Anyway, you will find alot of trainers and grass here, so be sure to fight them all so you can level up as much as you can. You will eventually come to a building with some Aqua members blocking a path. If you go inside, you will see a bed. Talk to it so you can heal up. There are a few Aqua members around here, so just beat them all and if you have an empty slot, you will get a Pokemon! It is Castform. It does not evolve, and is a normal type. However there is something different about it. It starts with Rain Dance, Sunny day and Hail. If you use any of those moves, its type and looks will change accordingly. Meaning it can become a water, fire or ice type. Now that is cool. Anyway, when you leave, your Rival will come up and give you HM02, Fly! However you need the next badge to use it out of battle. So lets go get it!