First off, it doesn’t matter which girl you start off with, but try to use one that will have a fetishes you want for a future line up. Personally I used Kyanna, but it hardly makes a difference which girl you pick. Skip all tutorials, you can get further faster without using them.
Day 1
Do 2-3 photoshoots to start off, then 2-3 cam shows. Invest in Staffing and hire your second girl. From here I recommend cycling the girls through cam shows and photoshoots to keep money coming in whilst still getting fans.

This is where getting girls with similar fetishes becomes really important.
For instance:
Initially I hired all three base girls. From there I hired who I could, but replaced girls in preference of fetish vs cost. So my line up built up to be: Nikki, Tiffany, Kyanna (all hired in the first 5 days), Lola, Zoey, Brooke and Aiko (hired from about day 5 to 10).
There is a problem here. Lola, Zoey, Brooke and Aiko are all smokers and/or drinkers. Without being able to use accessories this can really hinder a game’s progress. I recommend using a girl with low stats to do collect cigarettes and liquor when supplies get low. (I.e. Zoey) Pay attention to who you hire and how frequently they smoke or drink, it can be worth hiring someone with similar fetishes but a lower fan count if the other options are frequent/addicted smokers or drinkers.

Within the first few days I recommend buying a few cheap promos too, the more you buy now, the more fans you can buy later, and the quicker you’ll get to that 5K milestone.

Investments are best done around the 5-15 day area. Place a focus on Staffing early on, but don’t feel pressured to use as many girls as you can. I only used 7 and made it to 5K at about 15 days, so it’s not remarkably important. Capacity is useful as you want quite a few girls going into photoshoots and your main money makers into cam shows.
Ignore Inventory completely, you cannot use items for this achievement. Productivity and Automation are nice, but unnecessary, the first 2 tiers should be fine, beyond that it comes down to your preference on speed.

You can ignore Training, Community and Aesthetics for the most part, they’re not worth going past tier one if you’re particularly keen on using them, that money is better spent on promos. I didn’t use those investments at all for this save. Web Servers, Hardware and Advertising are important however. None of them need to be maxed, but the money is a must when it comes to other investments and promos, and Hardware investments will stop your photoshoot girls from becoming useless.

Who you put into cam shows and photoshoots is important, and should be decided based on how much money they make vs cost vs how many fans they make. Expensive girls with high talent should be a priority for cam shows and promos, and there should be at least one girl with a decent style level with one fetish in common doing photoshoots for every girl in a cam show. If there isn’t, they should be a priority when buying promos.
For the girls who are limited to photoshoots, level their style to the max and keep talent low. If a girl has similar talent/style levels, place them according to the number of fans they have and how much they cost. For example, Brooke has 5 style and 3 talent when hired, so she’s quite expensive to employ, because Glasses was one of my most popular fetishes, she was a cam girl (and quite profitable). Likewise Lola has 3 style and 3 talent when hired, but because ebony was a popular fetish she was a cam girl too.

Here is my line up with (style/talent) levels.
Cam girls: Nikki (3/2), Lola (3/3), Brooke (5/3), Aiko (2/4)
Photo girls: Kyanna (5/1), Tiffany (3/2), Zoey (4/1)

Some girls where flexible in that they could be either. Lola was initially a photo girl, but as ebony became more popular she was profitable as a cam girl. Tiffany and Nikki have the same style/talent levels, but Nikki’s fetishes were more popular and as Tiffany’s fan count became stagnant she was switched from a cam girl to a photo girl. Zoey was also profitable as a cam girl, but most often remained a photo girl to keep Lola’s fan count up and because her talent level was low and increasing it would cause her to become quite expensive.

Decide which promos to buy based on what fetishes your cam girls have. There’s not much point buying the ones for your photo girls because they earn their own fans and won’t produce a profit. Of course, buy those promos too, but only after the ones best suited for your cam girls. I didn’t bother with any fetish promos that were for items, but you could use them to get your fan count higher. They’re not necessary though, and you won’t make any money from them.

These were my fetishes day 20 (slightly differ by the endgame thanks to promos). My most popular fetish was Glasses and all three of my Glasses girls were camming.

In summary:
Hire girls based on fetish and cost.
Keep style/talent levels relevant to job. (Cam show or Photoshoot)
Investments should be based on promos, cash and fans.
All cam girls need a photo girl with one fetish in common or they are priority for promos.
Place girls based on profit and style/talent level.
Promos should be purchased based on profit and fan count.