I?m a beginner myself and I haven?t bothered with the Nintento Online thing or whatever, so I decided to do a little write-up for similar people who want to sweep through max raids as efficiently as possible while dealing with Eevee, Clefairy, Solrock, and Wobbuffett allies.
1a) Use level 100 Pokemon.
The levels of your allies is scaled at 70% of your Pokemon?s level. If you use a level 100, your allies will be level 70 which is the strongest possible.
1b) To get to level 100 easily, do the Battle Tower.
You don?t even need your own team to sweep the Battle Tower. Talk to the guy on the right counter and take his rental teams ?Skill Team? and ?Rain Team?. Sweep the 1v1s with the Skill Team (Gyarados and Falinks will clean it up). Sweep the 2v2s with the Rain Team (Pelipper + Barraskewda will win easily). This should give you enough Rare Candy to get to level 100, as well as a variety of other prizes. You need 33 wins in a row in each to claim max rank, taking about 3-4 hours.
2) Use a Pokemon with good stats.
A good Pokemon to start with would be a legendary such as Eternatus or Zacian. If you have money, you can pump vitamins to max their relevant attacking stats, but this is optional and not nearly as important as reaching level 100. A good way to make money quickly is to train a Gigantamax Meowth and farm the Champion Cup. Note that the Gigantamax Meowth money formula is as follows:
1st Gold Rush ? 100 x Level
2nd Gold Rush ? 200 x Level
3rd Gold Rush ? 300 x Level
Also, Amulet Coin doubles the income from Gold Rush, and the max income is 99,999 for one battle. To receive 99,999, you will have to level your Meowth to at least 84.
3) Use Choice items.
This is a raid. There is no strategy other than spamming the same attack over and over and using Full Restore when at low HP. Therefore, the best items to use would be either Choice Band or Choice Specs, depending on the Pokemon. You can pick up a free Choice Band on Route 2 and a free Choice Specs in the Spikemuth gym.
That?s about it. With a level 100 Specs Eternatus with max Special Attack, you will be fine for the majority of 5-star raids (some will require re-rolls if the allies are too severe). Any attack of yours will trigger the shields and then you?re just hoping for the allies to use attacking moves and not die. Usually, it?s enough. At that point, it becomes easy to farm many Exp Candies and therefore easy to train backup Pokemon to maximize type advantages.