I've been using interactive brokers for a while and would like to implement an automatic trade in a regular (say monthly) interval. For example I would like to dollar-cost or value average an amount or transfer a part of my salary to my interactive brokers account. How do I automate a simple order in a regular interval?
You do not. Interactive Brokers caters a very specific target crowd - and "I send money once per month, automatically invest it" is NOT it.
They rather want active trading investors, which you are not. Expect their services to cater to their target market.
Although I have made a number of withdrawals from my IB account to stay under SIPC limits, it has been nearly 20 years since I funded my IB account. My somewhat vague recollection of the process is that IB had a few extra verification hurdles in order to accomplish these. I don't know if the current deposit/withdrawal process is still the same or if it has been simplified.
Barring any complications on IB's end, transferring part of your salary to your IB account shouldn't be a problem since you can set up a recurring transfer from your bank to IB. As for implementing an automatic trade investment at IB on a regular basis, I dunno.
The obvious suggestion is that you should call IB.
Those brokers usually have investment plans on a limited amount of products - mostly funds and ETFs. For an automated investment, I think those products are much better shaped then single stocks.
I prefer ETFs because on average they beat managed funds and they are lot cheaper (TER).
I guess if you want to buy stocks, you have to do this yourself.