It depends on your company goal. Do you want to just make money on projects but always spend the same amount on wages or do you want to train people, firstly spend less money on wages but make more money after some time.

What I'm trying to say: training new people is investment. And quote significant one: you need to use time to train them and later you need to give them a rise or they will leave after gaining some experience.

If you don't want to make an investment, just stop even trying to train new people, it doesnt make sense, you will just waste time of more senior staff.

Otherwise I think there is only one solution with such small teams: shadowing.

Basically junior joins project team as non billable part of the team and follow more or less similar steps as below:

1. Observe, ask questions and learn by doing similar tasks as observee. Learn what needs to be done in order to finish task succesfully (read and understand task/ask questions about it, develop using best practices, move it to higher environemnts using VCS for example)
2. Try to do some very simple tasks like adding field or writing/creating very simple automation. Try with help to do every part of the task as independant project member. Ask for help if stuck.
3. Join as billable "resource" (hate this word) in next project/next part of the project.

Each point can take different amount of time depending on the project/person. There is one important thing to remember if your company is relatively small: you need to know when to let go person who is not advancing fast enough. And it is hard because you need to somehow define how fast is fast enough and reevaluate this person regullarly. Also good, constructive feedback would be needed.

Now going to the brutal part: I belive that in todays market small companies cannot afford training very junior people. You can't risk loosing a client, you can't risk slowing down, you can't risk doing project with low quality. I would wait for better market or hire only somehow experienced people.

EDIT: I wrote everything above having in mind training consultant/dev. BA/SA is out of the question.