From my exp, the best way is doing it manually. Select 4-5 main interests of your account for example crypto, anime, cars, baseball and cooking for example. Post some generic posts for each topic, make your profile look organical. After that simply find some related communities, open followers and follow them 1 after another (20-25 people each 1-2 hours). About a half of them will follow you back. Sometimes make new generic posts, comment smth neutral on groups and like some posts, if you only do following you can get shadowbanned easily. This is how you get real followers with the less risks of getting your account banned. You also get followers with the same interest, so they may also give you some engagement by liking, reposting and commenting, making it look like a real influencer account.
I agree that using bots to follow people gives you much more followers in a certain period of time, but keep in mind that the followers you get are less interested in content you post and knowing that twitter has really dumb banning algorhitms getting 5k followers account banned or shadowbanned is definitely not you are looking for. At least this is my way and so far it works well.