Baby Showers are fun!:) So first you need to look at this as a fun experience and dont overwhelm yourself too much. The positives about it is that your client seems to not be to picky about what she wpuld like her baby shower to which works in your favor because it allows you to pretty much delegate everything and do it the way you want it to be done. The first step you should do now is have your client create her guest list. This will be extremely helpful because it allows you to know the amount of people she will have to feed, and also to make sure that there will be enough space available to seat all guests. Next, have your client simply call, text, or email all of her guests asking them what they like to eat..nothing to elaborate, just enough to get the idea of what kind of food will be served. Make sure to include the question "Do you have any food allergies?" we all know why this is important! From personal experience, "finger-foods" are pretty common at baby showers...sandwhiches,meatballs,chicken,fruit..etc.
After this is figured out then you can go on to the entertainment of the "party" , this is an important part of the shower for me because you have to make sure you have enough games to keep all the guest engaged and of make sure that its fun!
Along with games, comes prizes so make sure that the budget is set out to have enough prizes for all the guest who will be attending.
There are many things to share about baby showers, i hope my info was a good enough help but if you are in need of more help dont hesitate to ask!